Every tool

Returns one representative colour for an image — mean, median or most frequent — as a colour asset.

Converts images to or from AVIF and reports the size against the JPEG or WebP equivalent.

Keys out a flat or single-colour background in OKLab and returns a transparent PNG, with a brush for fixing the edges.

Decodes a Base64 string or data URI back into a viewable, downloadable image.

Encodes an image into a short BlurHash or ThumbHash string for use as a loading placeholder.

Adds a solid, gradient or rounded border and padding around an image, or pads it to a target ratio.

Adjusts brightness, contrast, saturation, temperature and sharpness with a live histogram.

Arranges photos into a grid or mosaic layout with adjustable gutters, corners and background.

Re-renders an image as protanopia, deuteranopia, tritanopia or greyscale vision would see it.

Lays a folder of photos out as a printable index page with filenames and capture dates.

Strips camera, GPS and editing metadata from photos while leaving the pixels untouched.

Shows camera, lens, timestamp and GPS metadata embedded in a photo, as coordinates rather than on a map — drawing one would send the location to a tile server.

Proposes face boxes from a skin-colour heuristic — no model, so it also finds hands and misses shaded faces — for you to confirm or draw over, then mosaics them by rewriting the pixels.

Produces the whole favicon set — ICO, PNGs, Apple touch icon, web manifest — plus the HTML to paste.

Explodes an animated GIF or WebP into numbered frames with their per-frame delays listed.

Assembles a list of images into an animated GIF with per-frame delay, looping and palette control.

Renders typed text as if written with a ballpoint pen — per-letter jitter, baseline wobble and ink variation — on a transparent PNG.

Converts iPhone HEIC/HEIF photos to JPEG or PNG, keeping or dropping the original metadata.

Builds a multi-resolution .ico from an image, or unpacks the images inside an existing .ico.

Crops a portrait to the ID and passport sizes of Korea, Japan, China, Spain, Mexico and the US visa, swaps the background and lays out a print sheet.

Crops to a freeform or fixed-ratio region and can auto-trim uniform or transparent borders.

Compares two images pixel by pixel and highlights what changed, with a perceptual difference score.

Converts between PNG, JPEG, WebP, AVIF, GIF, BMP and TIFF, one file or a whole folder at a time.

Resizes by pixels, percentage or a target longest edge, with aspect-ratio lock and batch presets.

Cuts one image into an N×M grid or fixed-height slices and packages the pieces as a zip.

Joins images edge to edge horizontally or vertically — the long-screenshot case — with optional overlap trimming.

Encodes an image as a Base64 string or a ready-to-paste data URI for CSS, HTML or JSON.

Traces a bitmap into SVG paths, tuned for logos and line art rather than photographs.

Enlarges 2× or 4× with a directional interpolator that keeps diagonal edges sharp, with no model to download.

Combines images into a single PDF with page size, orientation, margin and ordering control.

Smooths the 8×8 blocking and ringing left by heavy JPEG compression or repeated re-saving.

Re-encodes a JPEG at a chosen quality with a live before/after size and a difference view.

Adds top and bottom caption text to an image with the outlined meme typography.

A scratch canvas built around the clipboard: paste a screenshot with Ctrl+V, draw on it, and Ctrl+C the result straight back out.

Pulls an N-colour palette out of an image and exports it as hex, CSS variables or an ASE swatch.

Removes sensor grain from high-ISO photos while keeping edges, with a strength slider.

Applies a mosaic or blur over selected regions of an image and flattens it into the output.

Generates a solid or gradient placeholder at any size with the dimensions drawn on it.

Quantises the palette and rewrites the deflate stream to shrink a PNG without changing its dimensions.

Develops DNG in the browser — own demosaic, as-shot white balance, the file’s colour matrix, exposure — to JPEG or PNG, and pulls the camera’s embedded JPEG out of CR2, NEF, ARW, RAF and other RAW containers.

Rotates by 90° steps or an arbitrary angle and mirrors horizontally or vertically.

Draws arrows, boxes, numbered steps and blur patches on a screenshot and exports a flat image.

Turns a photo of a signature on paper into a clean transparent PNG, removing shadows and paper texture.

Draw your signature with a mouse, finger or stylus and download it as a transparent PNG or SVG.

Packs many images into one atlas and emits the CSS or JSON frame map alongside it.

Generates a Korean name stamp — round or square, seal-script or plain — as a red-ink transparent PNG.

Cuts a person or an object out of an ordinary photo with an on-device segmentation model, and returns a transparent PNG with a soft, decontaminated edge.

Removes editor cruft, collapses transforms and rounds path precision, showing the rendered diff.

Renders an SVG to PNG, JPEG or WebP at any scale factor, with a transparent or filled background.

Trims transparent borders, flattens alpha onto a chosen colour, or extracts the alpha channel as a mask.

Stamps text or a logo across images with position, opacity, tiling and batch application.

Converts images to or from WebP, with a quality slider and lossless mode.

Reorders and pairs pages for saddle-stitch booklet printing, with signature size and creep control.

Builds or edits the outline tree, including generating one from headings or a pasted list.

Keeps or removes a page range such as "1-3,7,12-" and writes the result as a new PDF.

Typesets Markdown to PDF — headings, lists, tables, code blocks and quotes — with base-14 fonts. Korean text needs a font it cannot embed.

Lays 2, 4, 6 or 9 pages onto each sheet with adjustable margins and cut marks.

Adds page numbers, headers and footers with a start offset and a chosen numbering format.

Shows every page as a thumbnail so you can reorder, duplicate, rotate or delete them.

Adds highlights, notes, shapes and freehand ink, and exports the comment list separately.

Diffs two PDFs both as text and as rendered pixels, listing insertions, deletions and moves.

Downsamples embedded images, subsets fonts and drops unused objects to reduce file size.

Trims page margins uniformly or per page, with automatic detection of the content box.

Fills in a received PDF for submission: tick checkboxes, type text and dates, place a signature or stamp, then flatten.

Merges annotations, form fields and layers into the page content so they cannot be edited or hidden.

Reads the filled field values out of one or many form PDFs into a single table.

Fills AcroForm fields by hand or from a CSV row, and can flatten the result so it cannot be edited.

Lists every embedded image with its resolution and exports the ones you pick at original quality.

Rewrites a PDF into the linearised layout of ISO 32000-1 Annex F — first-page section, page offset and shared object hint tables, split cross-reference — and reports how few bytes page 1 now needs.

Joins several PDFs into one, with drag-to-reorder and per-file page ranges.

Views and removes author, producer, creation dates, XMP blocks and embedded file attachments.

Scales and centres page content onto a different paper size such as A4, Letter or B5.

Encrypts a PDF with an open password and/or a permissions password — AES-256 by default, AES-128 and RC4 for old readers — and sets printing, copying, editing and annotation permissions.

Removes the open password or permission restrictions from a PDF you can already open, given its password — RC4 and AES files alike — and writes it back in the clear.

Deletes the underlying text and image content inside marked areas, not just a black rectangle on top.

Rebuilds a broken cross-reference table and recovers the readable pages of a damaged PDF.

Rotates chosen pages by 90° steps and can auto-orient pages from the text direction.

Splits a PDF at chosen page breaks, every N pages, or on bookmark boundaries.

Walks the object tree, listing fonts, colour spaces, JavaScript, attachments and per-page byte weight.

Finds ruled tables from the lines drawn on each page — merged cells included — and borderless ones from aligned columns, then exports each as CSV or TSV. Values are as printed; column types are not guessed.

Pulls the text layer out of a PDF in reading order — columns, rotated pages and Korean CID fonts included — as plain text or Markdown, and names any font it could not decode.

Overlays text or an image watermark on every page with angle, opacity and layer position.

Converts to PDF/A-2b or PDF/A-1b — XMP identification, an sRGB output intent computed from IEC 61966-2.1, no encryption, no scripts — and refuses, with reasons, when a font is not embedded or a page paints in CMYK.

Checks a supposedly redacted PDF for text, images or metadata still hiding under the black boxes.

Thresholds a scanned PDF to bilevel, despeckles, crops to the ink and can drop blank pages. It does not OCR or deskew.

Converts between MP3, WAV, FLAC, AAC, OGG and Opus with bitrate and sample-rate settings.

A chainable rack in one page: reverb by convolution with generated impulse responses, delay, chorus, flanger, EQ, compressor, fade and peak normalisation. The order of the chain is editable, because it changes the result.

Joins audio files end to end or mixes them onto one timeline with per-track gain.

Cuts a section out of an audio file on the waveform, with fade in and fade out.

Renders an audio track as a waveform, spectrogram or frequency-bar image (PNG), for artwork and thumbnails.

Estimates a track’s tempo in BPM by onset autocorrelation, with a confidence score and alternative candidates.

Renders an SRT, VTT, ASS or SMI file permanently into the video frames with size, position, colour and outline control, drawn with the browser’s own fonts so Korean needs nothing extra.

Subtracts what is identical in both channels, band-limited so the bass and the top survive. This is not stem separation: it removes the centred kick, bass and snare along with the vocal, leaves any stereo reverb behind, and does nothing at all to a mono file — which it detects and refuses up front.

Pulls the audio track out of a video as MP3, WAV, M4A or FLAC, or copies it without re-encoding.

Lists the soft subtitle tracks inside an MKV or MP4 and exports the chosen one as SRT or VTT.

Exports frames at a timestamp, at a fixed interval, or every frame in a range as images.

Converts an animated GIF to MP4 or WebM, which is usually a fraction of the size.

Measures integrated loudness and true peak, then normalises to a target LUFS such as -14 or -16.

Reads and edits container metadata — title, artist, album art, codecs, duration and streams.

Removes hiss, hum and room noise with spectral gating: a noise profile from a marked region or the quietest tenth of the recording, subtracted per frequency band with a stated floor. Reads audio files and the audio track of MP4/WebM; writes WAV, M4A or Opus.

Detects a monophonic vocal’s pitch with YIN, snaps it to a chosen key and scale, and resynthesises with TD-PSOLA so the formants stay put. The retune-speed control runs from natural correction to the hard-tuned staircase; the detected pitch track is drawn.

Strips the audio track from a video without touching the video stream.

Plays a clip backwards, decoding one keyframe interval at a time so memory stays bounded, with the audio reversed sample by sample or muted. Refuses, with the numbers, when a keyframe interval would not fit the memory cap.

Finds quiet stretches in a recording and removes them, with a threshold and padding setting.

Speeds up or slows down a video from 0.25× to 4×. The picture is retimed frame-exact; the audio keeps its pitch through WSOLA time-stretching, or can follow the speed tape-style, or be muted.

Converts between SRT, VTT, ASS, SMI and plain text, fixing the encoding along the way.

Shifts or stretches subtitle timings by a fixed offset or by matching two reference points.

Changes playback speed without shifting pitch, or transposes pitch without changing length.

Re-encodes to a target file size or a quality preset, stepping the resolution down when the bitrate would starve it, and shows the projected size before it starts and the actual size after.

Reads MP4, MOV, WebM and MKV and writes MP4 (H.264 + AAC) or WebM (VP9 + Opus) with quality and resolution settings. When only the wrapper changes — MOV to MP4, MKV to WebM — the streams are copied untouched.

Crops the frame with a draggable window locked to 9:16, 1:1, 16:9, 4:5 or free, or pads it with bars to a target ratio, then re-encodes on your device.

Assembles clips into a YouTube or Shorts upload in the browser: trim, order, transitions, a music bed and subtitles. Same-batch AI clips with hard cuts export losslessly without re-encoding.

Concatenates clips in order, normalising resolution and frame rate when they differ.

Rotates a sideways phone recording by 90° steps, or rewrites just the rotation metadata.

Analyses camera motion across frames and re-crops each one to smooth out handheld shake.

Builds a grid of evenly spaced frames with timestamps, the classic preview contact sheet.

Turns a clip into an animated GIF or WebP with frame rate, size and palette controls.

Cuts a clip between two timestamps, copying streams without re-encoding when the cut is on a keyframe.

Overlays a logo image or a line of text at one of nine anchors with margin, size, opacity and an optional time window.

Dudley’s channel vocoder: splits a voice into N bands, follows each band’s envelope and paints it onto music or a built-in synth drone. Controls for band count, attack, release, formant tilt, sibilance pass-through and dry/wet.

Shifts pitch and formants independently, so a recording reads as a different person rather than as a sped-up tape. Presets for male↔female, child, giant, helium, robot (ring modulation), telephone (300–3400 Hz band) and whisper (noise excitation). Records from the microphone or takes a file; writes WAV.

Draws the waveform of an audio file as an image or SVG with colour and size options.

Converts between UPPER, lower, Title, Sentence, camelCase, snake_case, kebab-case and CONSTANT_CASE.

Reduces accented Latin text to plain ASCII — café becomes cafe — for slugs, sorting and search keys.

Removes duplicate lines, keeps only duplicates, or counts how many times each line appeared.

Guesses a file’s character encoding — CP949, Shift_JIS, GB18030, Windows-1252 and more — with a side-by-side preview of each candidate, then re-saves it as UTF-8 (with or without BOM), UTF-16 or EUC-KR/CP949.

Replaces text by literal, whole word or regular expression, with capture groups and a preview of every hit.

Converts pasted HTML or a saved page into clean Markdown — headings, nested lists, GFM tables, fenced code — dropping scripts and styles.

Finds and strips zero-width spaces, BOMs, soft hyphens and bidi controls hidden in pasted text.

Joins broken lines back into paragraphs, keeping blank-line boundaries intact.

Adds or removes leading line numbers with a start value, step, padding and separator.

Sorts lines alphabetically, numerically, by length or randomly, with reverse and case options.

Hard-wraps text at a column width, or unwraps it back into single-line paragraphs.

Turns lines into a comma list, quoted SQL IN clause, JSON array or bullet list, and back again.

Generates placeholder paragraphs, sentences or words in Latin, English, Korean, Japanese or Chinese.

Edits Markdown with a live preview and exports the rendered HTML, with GFM tables and task lists.

Edits a table as a grid and emits aligned Markdown, or reformats a messy pasted table.

Pulls every email, URL, number, date or custom regex match out of a blob of text into a list.

Scores English text with Flesch–Kincaid and friends, and estimates reading time in both languages.

Turns a title into a URL-safe slug, with romanisation for Korean and a choice of separator.

Fills a {{placeholder}} template once per row of a table and returns one document per row.

Finds emails, phone numbers, card numbers and IDs in free text and masks or pseudonymises them.

Compares two texts side by side or inline, at line, word or character granularity.

Reverses a string, the words in it, or the order of lines — grapheme-aware, so emoji survive.

Splits a long text into chunks by line count, character budget or a delimiter, keeping sentences whole.

Converts text to and from binary, octal, decimal or hexadecimal in a chosen encoding.

Breaks text into codepoints with names, blocks, scripts and UTF-8/UTF-16 byte sequences.

Applies NFC, NFD, NFKC or NFKD — the fix for Korean text from macOS that looks right but never matches.

Trims trailing spaces, collapses runs of blanks, converts tabs and removes empty lines.

Counts characters with and without spaces, words, lines, paragraphs and UTF-8 bytes.

Counts how often each word or n-gram appears, with Korean-aware tokenising and a stopword list.

Parses a .env file and converts it to JSON, YAML, shell exports, Docker or Kubernetes formats.

Builds a .gitignore by combining language, framework and editor templates, with duplicates merged.

Renders a table as monospaced ASCII, Markdown or box-drawing borders for READMEs and comments.

Encodes and decodes Base64 and Base64URL for text or files, handling UTF-8 correctly.

Hashes a password with bcrypt at a chosen cost and checks a password against an existing bcrypt hash. Detects argon2 but does not compute it.

Parses a PEM or DER certificate or CSR and shows subject, SANs, validity, key usage and chain hints.

Converts between octal, symbolic and checkbox permission views, including setuid and sticky bits.

Renders a code snippet as an image with syntax highlighting, a window frame and a chosen theme.

Builds a cron expression field by field, each typed into its own box with its legal range beside it, and shows the resulting schedule as you change it.

Explains a cron expression in plain language and lists the next runs in a chosen timezone.

Formats or minifies CSS without reordering anything, preserving the token stream exactly.

Converts a curl command into fetch, axios, Python requests, Go, PHP or PowerShell.

Opens an exported image tarball and shows each layer’s command, size and the files it added or deleted.

Turns a docker run command line into a compose service definition, and converts back the other way.

Hashes files of any size in a streaming pass and compares the result against a pasted expected value.

Formats queries and SDL, validates a document against a schema and prints the type it resolves to.

Opens a HAR capture as a waterfall and strips cookies, auth headers and tokens before you share it.

Shows any file as an offset/hex/ASCII dump, identifies the magic bytes and highlights a search hit.

Computes an HMAC over a message with a chosen hash and key encoding, for webhook signature checks.

Formats or minifies HTML, preserving inline elements and optionally collapsing whitespace.

Escapes and unescapes HTML entities, with named, decimal and hexadecimal output.

Explains every status code with its spec meaning, cacheability and the mistakes people make with it.

Strips comments and whitespace from JavaScript or TypeScript without renaming anything, and re-indents a minified bundle so it can be read again.

Runs jq 1.7 filters against pasted JSON in the browser with a cheatsheet, and hands you the matching command line.

Flattens nested JSON into columns or rebuilds objects from a table, with a dot-path column naming rule.

Converts between JSON and TOML, mapping nested objects onto table headers.

Converts between JSON and XML with configurable handling of attributes, arrays and text nodes.

Converts either way, preserving key order and choosing block or flow style for the YAML side.

Compares two JSON documents structurally, ignoring key order and reporting added, removed and changed paths.

Pretty-prints, minifies and validates JSON, pointing at the exact line and column of a syntax error.

Converts between NDJSON and a JSON array, and reports the number of any line that will not parse instead of stopping.

Validates a document against a JSON Schema and reports each failure with its instance path.

Generates Go structs with json tags from a JSON sample, including nested and repeated types.

Infers a JSON Schema from one or several samples, unioning the shapes it sees.

Generates serde-annotated Rust structs from a JSON sample, with Option for nullable or missing fields and snake_case renames.

Infers TypeScript interfaces or types from a JSON sample, merging optional and union fields.

Builds a Zod schema from a JSON sample, with nullable, optional and enum inference.

Runs a JSONPath expression against a document and highlights the matched nodes as you type.

Fetches a JWKS endpoint, picks the key by kid and verifies a token’s signature and standard claims.

Decodes header and payload, shows claim expiry in local time, and checks the signature against a supplied key.

Generates RSA, ECDSA or Ed25519 key pairs and exports them as PEM, JWK or OpenSSH.

Decodes every Base64 value in a Secret manifest, and re-encodes an edited one ready to apply.

Compares common open-source licences by obligation and compatibility and emits the LICENSE file.

Looks up a MIME type from an extension or the other way round, and sniffs the type from file bytes.

Compares two OpenAPI documents and separates breaking changes from additive ones.

Checks an OpenAPI document for missing responses, unused schemas, references that point at nothing and the other faults that break code generators.

Decodes a protobuf payload without the .proto file, inferring field numbers, wire types and nesting.

Breaks a regular expression into a labelled tree so you can read what each part actually matches.

Tests a regular expression against sample text with live match highlighting and capture group listing.

Checks which versions satisfy a range, compares two versions and sorts a list in precedence order.

Maps a minified stack trace back to original files and lines using a source map you supply.

Formats SQL with configurable keyword case, indentation and comma placement, across major dialects.

Generates an OpenSSH key pair with a comment and shows the fingerprint. The private key comes out unencrypted — add a passphrase locally with ssh-keygen -p.

Escapes and unescapes strings for JSON, JavaScript, SQL, shell, CSV and regular expressions.

Encrypts a message with AES-GCM from a passphrase and produces a self-contained Base64 blob.

Computes MD5, SHA-1, SHA-256, SHA-384, SHA-512 and CRC-32 of a string, with an uppercase and Base64 output option.

Formats and validates TOML, normalising table ordering and inline-table style.

Generates sortable ULIDs or short NanoIDs with a chosen alphabet and length, and shows collision odds.

Percent-encodes and decodes URLs and query values, with a component-versus-whole-URL mode.

Breaks a user-agent string into browser, engine, OS and device, and shows your own for comparison.

Generates UUID v1, v4, v5 and v7 in bulk, and decodes the timestamp out of a v1 or v7 value.

Lists imports, exports, memory and section sizes of a .wasm module and prints its text format.

Indents XML and reports the line and column of the first well-formedness fault.

Evaluates an XPath or CSS selector against XML or HTML and lists every matched node.

Re-indents YAML consistently, validates it, and flags the tab and anchor mistakes that break parsers.

Runs a two-proportion z-test and a chi-square test on two conversion rates with Wilson confidence intervals, and computes the sample size for a target effect and power.

Performs exact arithmetic on numbers far beyond 64 bits, including power, modulo and factorial.

Counts working days between dates, or finds the date N working days out, excluding weekends and holidays.

Profiles each column with count, nulls, unique values, min, max, mean, median and distribution.

Projects the value of a lump sum or regular deposits at a given rate, with a year-by-year table.

Trims cells, normalises headers, fixes number and date formats and reports rows with the wrong column count.

Removes duplicate rows on all or selected key columns, keeping the first, last or most complete row.

Filters rows with column conditions, sorts on several keys and picks the columns to keep.

Joins two tables on a key column with inner, left, right or outer semantics and shows unmatched rows.

Splits a table by row count or by the distinct values of a column, into separate files with the header repeated in each.

Generates CREATE TABLE and INSERT statements from a table, with inferred types and a chosen dialect.

Opens a large delimited file with type detection, column stats and sorting, without loading it all into memory.

Converts between about thirty currencies at the ECB’s daily reference rates, crossed through the euro, or at a rate you type in.

Converts bytes, KB, MB, GB and TB in both decimal and binary conventions, and computes transfer times.

Adds or subtracts days, weeks, months or years from a date, optionally skipping weekends and holidays.

Counts days, weeks, months and years between two dates, with a D-day view and business-day option.

Computes mean, median, mode, variance, standard deviation, quartiles and outliers from pasted numbers.

Solves linear, quadratic and cubic equations with the working shown, finds real roots of other equations numerically, and solves linear systems by elimination.

Factorises an integer and computes GCD, LCM, divisors and primality for one or several numbers.

Adds, subtracts, multiplies and divides fractions, reduces them and converts to and from decimals.

Multiplies, inverts, transposes and row-reduces matrices in exact rational arithmetic, and finds determinant, rank and trace.

Converts between binary, octal, decimal, hexadecimal and any base up to 36, with bitwise views.

Adds or removes thousand separators, rounds to a set precision and formats as currency or percent by locale.

Works out percentage of, percentage change, discount, markup and reverse percentage in one place.

Groups rows by one or two columns and aggregates with count, sum, average, min, max or distinct.

Draws a bar, line, area, pie or scatter chart from a table with round-number axes and a legend, and exports it as SVG or PNG.

Fits a linear, polynomial, exponential, logarithmic or power model to paired data and reports R², Pearson r, Spearman ρ and residuals.

Converts between Roman numerals and Arabic numbers, validating subtractive notation.

Runs SQL against dropped CSV or TSV files in the browser — SELECT, WHERE, GROUP BY/HAVING, ORDER BY, LIMIT, CASE and a two-table JOIN — with the grammar on the page.

Compares two tables by a chosen or inferred key column and lists added, removed and changed rows cell by cell, side by side or as a change log.

Adds and subtracts hh:mm:ss durations, totals a column of times and converts to decimal hours.

Converts a moment across timezones and shows a shared-hours grid for scheduling across regions.

Converts length, weight, area, volume, temperature, speed, pressure and data units, including Korean units.

Converts between epoch seconds, milliseconds, ISO 8601 and human dates in any timezone.

Generates EAN-13, UPC, Code128, Code39 and ITF barcodes with check digits and print-ready output.

Extracts up to 100 links from a page, or takes a pasted list, and checks each in parallel — status, redirect target and response time, HEAD first and GET when refused.

Generates a certificate signing request and its private key from subject fields and SAN entries.

Queries A, AAAA, CNAME, MX, TXT, NS, SOA, SRV, CAA and PTR records over DoH, with TTL and the DNSSEC bit shown, from Cloudflare or Google.

Queries the same record from public DoH resolvers — Google, Cloudflare, Quad9, OpenDNS, AdGuard, NextDNS, Mullvad, DNS.SB, AliDNS — and shows which still hold the old answer.

Parses raw email headers into a delivery timeline with per-hop delays, reads the receiving server’s SPF, DKIM and DMARC verdicts, and flags From/Reply-To/Return-Path mismatches.

Fetches a URL and shows the full response headers, redirect chain, timings and compression used.

Composes and sends a GET/POST/PUT/PATCH/DELETE/HEAD request with custom headers and a body, and shows the status, headers, body and timing — without ever forwarding cookies or Authorization.

Shows your public IP or any address with its reverse name, ASN, announcing network, prefix and registry country from Team Cymru’s DNS data — no city-level geolocation.

Reads Open Graph and Twitter card tags from a URL and renders how the link will look when shared.

Identifies the hardware vendor from a MAC address OUI prefix and normalises the address format.

Checks a domain’s MX, SPF, DKIM and DMARC records together and explains why mail would be rejected.

Shows your public IP, its network and everything this tab reveals — browser, screen, language, time zone, connection — and names what a website genuinely cannot see, starting with your MAC address.

Tests whether a single TCP port on a host you specify accepts connections, and reports the banner.

Converts internationalised domain names to and from punycode and warns about lookalike characters.

Reads QR codes and common barcodes from an uploaded image, a screenshot or the camera.

Makes a QR for a URL, text, wifi, vCard or payment string, with error correction, logo and SVG export.

Follows a shortened or tracking URL through every redirect and shows the final destination.

Fetches robots.txt and the sitemap, tests whether a URL is crawlable and validates the sitemap format.

Builds valid SPF and DMARC TXT records from a guided form and explains each mechanism it emits.

Connects to a host, shows the served chain, expiry, protocol and cipher support, and flags chain gaps.

Expands a CIDR block into network, broadcast, usable range and host count, for IPv4 and IPv6.

Splits a URL into its parts, shows query parameters as an editable table and rebuilds the result.

Opens a WebSocket connection, sends frames you compose and logs everything received with timings.

Shows domain registration, registrar, nameservers and expiry, plus RDAP data where it exists.

Creates Apache or nginx basic-auth entries with bcrypt, APR1 or SHA hashing.

Opens a zip without extracting it and flags path traversal entries, executables, macros and zip bombs.

Decodes a Google Authenticator migration QR into the individual accounts and their secrets.

Checks whether a password appears in Have I Been Pwned’s breach data, sending only the first five characters of its SHA-1 hash from the browser (k-anonymity).

Sends the preflight a browser would send from a chosen origin plus a GET with that Origin, and explains by the Fetch standard’s rules exactly which header blocked it.

Builds a Content-Security-Policy from a guided form or from a report, and explains each directive.

Gives you a throwaway inbox that receives mail for a limited time, with attachments viewable in place.

What Gmail, Outlook, Apple Mail, Yahoo, Samsung Mail and Thunderbird support in HTML email, from caniemail’s device tests, with the date each was last tested.

Measures the Shannon entropy of a string or file and shows a byte histogram — useful for spotting keys.

Encrypts any file with AES-256-GCM from a passphrase, and decrypts files it produced.

Guesses which algorithm produced a hash from its length, charset and prefix, ranked by likelihood.

Builds an email from blocks as table-based, inline-styled HTML with a VML-backed button, and writes the plain-text alternative from the same blocks.

Checks an email’s HTML against what each mail client actually supports, points at the element that breaks, and shows what survives Gmail, Outlook and the rest side by side.

Opens PKCS#12, JKS or PEM bundles and lists the certificates, chains and key algorithms inside.

Removes author, device, GPS and revision metadata from documents, images, audio and video in one pass.

Extracts VBA projects from .docm/.xlsm/.pptm and legacy .doc/.xls, shows each module’s source with auto-run procedures and risky calls highlighted, and lists external links, DDE fields and Excel 4.0 macro sheets.

Builds an otpauth:// URI from issuer, account and secret and renders the QR an authenticator app can scan.

Builds a diceware-style passphrase from a word list, showing the entropy in bits.

Converts a password-manager CSV export between 1Password, Bitwarden, Chrome/Edge, KeePass, KeePassXC and LastPass layouts, with the column map for each documented.

Generates random passwords with length, character set and ambiguous-character rules, in bulk if needed.

Estimates how long a password would take to crack, naming the patterns that weaken it.

Encrypts and decrypts OpenPGP messages with a passphrase, entirely in the browser — RFC 4880 symmetric mode (AES-256, SHA-256 S2K, MDC), interoperable with gpg -c. Public-key encryption and signatures are not built.

Generates cryptographic random bytes as hex, Base64 or Base64URL at a chosen length, for app secrets.

Scans pasted code, logs or a config dump for API keys, tokens and private keys, with entropy heuristics.

Grades a site’s HSTS, CSP, frame, referrer and permissions headers and shows what to add.

Encrypts a note in the browser and gives you a one-time link that destroys the note after it is read.

Send a draft to a disposable address from your own account and see what the sending path rewrote — links wrapped in redirects, dropped style blocks, added beacons, the encoding used.

Computes the Subresource Integrity attribute (sha256/384/512) for a script or stylesheet you paste or drop in.

Inspects a link’s shape before you open it — lookalike characters, IP-literal hosts, @ tricks, deep subdomains, odd ports, shorteners — and on request traces its redirects and looks up the domain’s registration date. No reputation database.

Turns a TOTP secret into the current six-digit code with a countdown, for testing 2FA setups.

Works out the missing dimension for a target ratio and lists the standard sizes it matches.

Generates tileable SVG patterns — stripes, dots, grids, noise — with colour and scale controls.

Shapes each corner independently, including the two-value squircle syntax, and emits the CSS.

Composes layered box and text shadows with a live preview and emits the CSS.

Converts a colour between HEX, RGB, HSL, HWB, LAB, LCH and OKLCH and names the nearest known colour.

Picks a colour on an OKLCH field, with a screen eyedropper or from an uploaded image, and copies it in any notation.

Scores a foreground and background pair against WCAG 2 and APCA and suggests the nearest passing colour.

Stacks blur, brightness, saturation, hue and drop-shadow filters on a sample and emits the CSS.

Builds linear, radial and conic gradients with draggable stops and emits the CSS, in sRGB or OKLCH.

Lays out a grid visually with named areas and emits the grid-template CSS.

Pulls colours, spacings, radii and fonts out of a stylesheet and proposes a custom-property set.

Builds a 50–950 ramp from one colour and mirrors it into a dark one, so each token pair keeps its contrast.

Places a screenshot inside a phone, tablet, laptop or browser frame with a background and shadow.

Edits a cubic-bezier or spring curve against an animated preview and emits the CSS timing function.

Toggles every flex property on a live example and shows the CSS and what each property changed.

Computes a clamp() expression that scales a size smoothly between two viewport widths.

Converts TTF and OTF to WOFF and back in the browser and emits the matching @font-face rule; WOFF2 needs Brotli and is refused with a pointer to desktop tools.

Opens a font file to show its glyph coverage by block, Korean syllable count, weight, variable axes, embedding permission and licence name records.

Suggests heading and body font pairs from system font stacks, previewed with your own Korean and English text, and hands you the CSS.

Cuts a TrueType font down to the glyphs your text actually uses and can wrap the result as WOFF — the difference between a 4 MB and a 90 KB Korean webfont.

Finds the closest Tailwind palette entry to any colour and shows the perceptual distance.

Builds a harmonious palette from a base colour using complementary, triadic and analogous rules.

Converts RGB to CMYK with the plain formula (no ICC or paper profile) and flags saturated colours a four-ink press will dull.

Composes a 1200×630 share image from a title, subtitle, brand line and optional logo on a chosen template, and writes the meta tags to go with it.

Edits an SVG next to its live render and explains the file: viewBox and scaling, transforms, every path command, inherited paint, wasted bytes, and what breaks in an <img>, a data URI or inlined.

Converts path data between absolute and relative commands, moves, scales, rotates and reverses it, and shows the bounding box with a live preview.

Encodes an SVG as a CSS background data URI, escaping only what needs escaping to keep it small.

Generates a 50–950 lightness scale from one colour with perceptually even steps, ready as design tokens.

Builds a modular type and spacing scale from a base size and ratio, exported as CSS or tokens.

Builds Google, Outlook.com, Office 365 and Yahoo calendar links plus a downloadable .ics that Apple Calendar and Outlook desktop read.

Splits a bill evenly or by weighted share so the parts sum to the total exactly, and turns what people already paid into who-pays-whom transfers.

Opens a browser bookmark export, finds duplicates, empty folders and favicon bloat, and writes a cleaned file back. Dead-link checking is not possible in a browser and is not claimed.

Counts down to a duration or to a target moment, with a large display, a chime and a system notification.

Renders Mermaid flowcharts, sequence diagrams and pie charts as you type with its own parser and layout, lists exactly which syntax it supports, and exports SVG or PNG.

Turns a task table — typed in or pasted as CSV — into a Gantt chart on a day, week or month scale with dependency arrows, milestones, a today line and weekend shading, exported as SVG or PNG or printed.

Marks daily habits on a 14, 30 or 60 day grid and shows streaks and completion rates per habit.

Adds up what a meeting is costing in real time from attendee count and hourly rates.

Runs focus and break cycles with a notification, a session log and configurable interval lengths.

Sorts tasks into urgent/important quadrants by dragging or from the keyboard, and exports the result as Markdown.

A plain-text scratchpad that saves as you type and survives a reload, with a word count.

Records a tab, window or screen with optional microphone and system audio, and saves the WebM or MP4 locally.

Times elapsed intervals with lap splits and exports the laps as a table.

Starts and stops one timer at a time per task, then exports a CSV timesheet totalled by task and by day, with optional billing increments.

Keeps a checklist in your browser with due dates, tags and keyboard-first editing, exportable as Markdown.

Shows several cities at once with their offsets and marks the hours everyone is awake.

Converts between vCard, CSV and Google or Outlook contact exports, merging duplicate entries.

Writes one or many CSV files into an .xlsx workbook with typed columns, a header row and filters.

Fills {{placeholder}} fields in a .docx template once per CSV row — even when Word split a field across runs — and zips one document per row.

Counts words, characters and pages across .docx, .pptx, PDF and text files, for translation quotes.

Builds an EPUB 3 from Markdown, HTML or plain text with chapters split at headings, and reads an EPUB back out as Markdown or plain text.

Exports each sheet of an .xlsx or .xls workbook to CSV with the encoding and delimiter you choose.

Pulls every embedded image out of a .docx, .pptx or .xlsx at original resolution.

Builds a 거래명세서, 견적서 or 청구서 from line items with VAT separate, included or none, validates business numbers, and prints to PDF or saves XLSX.

Lays a CSV onto Formtec, AnyLabel or 3M label sheets (or a custom grid) with exact mm positions, a start slot and offset nudges, as a print-ready page.

Renders Markdown into a .docx with proper heading styles, so it can be edited and tracked in Word.

Unmerges cells, fills the gaps left behind, drops decoration rows and turns a report into a flat table.

Diffs two .docx files paragraph by paragraph with word-level marks inside changed paragraphs, side by side or unified, and exports an HTML or text report.

Converts .docx into Markdown, mapping headings, lists, tables and footnotes and extracting images.

Combines many workbooks or sheets into one, stacking rows or adding each source as its own sheet.

Splits a workbook into one file per sheet, or one file per distinct value of a chosen column.

Computes the year’s 24 solar terms to the minute of 절입시각, with the 삼복 dates and which term today falls in.

Estimates acquisition tax on a home or other property — the 1–3% progression, 8%/12% multi-home surcharges by your region choice, 지방교육세, 농어촌특별세 and the first-home relief.

Writes a number as the formal Korean amount used on contracts — 일금 오백만원정 — and back again.

Works out how many paid leave days have accrued by joining date or fiscal year, including the first-year rule.

Identifies the likely bank from an account number’s length and prefix and normalises the formatting.

Repairs Hangul mangled by a CP949/UTF-8 mix-up by trying every plausible encoding path and previewing each.

Checks the 10-digit check sum of a Korean business number and can bulk-validate a pasted column.

Estimates capital gains tax on a house, land or 분양권 from prices, dates and expenses — 장기보유특별공제 표1/표2, the 12억 1세대 1주택 rule, short-term rates and the 조정대상지역 surcharge you choose.

Estimates 종합소득세 from business, salary and other income with 인적공제, pension deduction, 자녀·표준세액공제 and 지방소득세, showing every step; expense ratios and itemised credits are entered, not looked up.

Reads 배달의민족·쿠팡이츠·요기요 settlement CSVs by column name, totals the fees, and matches each payout against your bank statement by amount and date, listing what never arrived.

Opens NTS e-tax invoice XML files (or a zip of them) into a table of supplier, buyer, items and tax, and checks that the items, totals, VAT rate and business numbers agree.

Draws the four pillars for a birth moment from the solar terms and the sexagenary cycle, counts the five elements and names the ten gods against the day stem, with the true-solar-time correction for the hour pillar.

Computes the 3.3% withholding on freelance income both ways — from gross and from the amount received.

Extracts initial consonants from Hangul and matches a list against a 초성 query — ㄱㅁㅇ finds 감마원.

Converts Hangul to Roman letters under the Revised Romanisation rules, with name and passport modes.

Reads Hanja as Hangul with 두음법칙 applied at word starts, offering every reading of an ambiguous character, and lists the Hanja for each syllable of a Korean word — readings only, no meanings.

Scores the 84-point housing subscription total from dependants, no-home period and account age.

Converts a deposit into monthly rent and back at a given conversion rate, against the statutory cap.

Turns a KakaoTalk export (PC, Android, iPhone, Mac CSV) into per-person counts and shares, hourly and weekday charts, a day-by-hour heatmap, median reply times, emoji and frequent words.

Works out your 만나이, 연나이 and the old 세는나이 from a birth date, on any reference day.

Counts characters with and without spaces and in bytes, matching how application forms count them.

Recovers text typed with the wrong input mode and converts between the 2-set and 3-set layouts.

Lists public holidays and substitute holidays for a year, including the lunar-dated ones, as a calendar or ICS.

Flags spacing, spelling and particle mistakes in Korean text and explains the rule behind each one.

Builds a repayment schedule for equal-payment, equal-principal or interest-only loans, with early repayment.

Picks number sets with exclusions and fixed numbers, and checks a saved set against past results.

Converts between lunar and solar dates, handling leap months, and lists a lunar birthday for years ahead.

Converts between hourly, monthly and annual pay at the statutory minimum, including the weekly holiday allowance.

Works out take-home pay from a gross salary after the four insurances, income tax and local tax.

Identifies the courier from an invoice number’s format, validates its check digit and builds the tracking link.

Reads a pasted payslip (text or CSV) into allowance and deduction items, checks the totals add up, and recomputes the four insurances and local tax against the current tables.

Reads the text of a property register (등기사항전부증명서) into 표제부·갑구·을구, lists the ownership history and live mortgages with their total, and flags 가압류·가처분·압류·경매·임차권.

Converts between 평 and square metres and shows the common apartment sizes each value corresponds to.

Checks whether a 13-digit resident number is structurally valid — date part, region rules and check digit.

Finds resident numbers in text or a spreadsheet column and masks them to the legally acceptable form.

Calculates statutory severance from the average wage of the last three months and the service period.

Splits national pension, health, long-term care and employment insurance between employee and employer.

Estimates the daily benefit and payment period from age, insured period and average wage.

Adds or removes the 10% VAT and splits a total into supply value and tax for invoice lines.

Calculates annual vehicle tax by engine displacement and vehicle age, with the prepayment discount.

Gives the Korean animal sign, the sexagenary year name and the star sign for a birth date.

Builds an animation of character grids from a video, a GIF, a frame-by-frame editor, moving text or a procedural effect, and exports plain frames, ANSI, asciicast v2, an animated GIF and a self-contained HTML player.

Draws boxes, lines, arrows and labels on a character grid, deriving every corner and junction from which neighbours are occupied, in Unicode box drawing or pure ASCII.

Renders text as large ASCII letters through a real FIGfont renderer, with two bundled fonts and a slot for a .flf of your own.

Generates a deterministic identicon or initials avatar from a name or email, as SVG or PNG.

Builds printable bingo cards from a word list or number range, each card shuffled differently.

Plots the three classical sine curves from a birth date, marks the days each crosses zero, and states plainly what the theory is worth: it has been tested against accidents, exams and mortality and found to predict nothing.

Converts an image into half blocks, quadrants or sextants with an ANSI truecolor foreground and background in every cell, and exports ANSI, HTML, SVG and PNG.

Turns a photograph into Unicode braille cells — 2 × 4 dots per character, eight times the resolution of a brightness ramp — with a choice of dithering.

Converts text into Unicode braille cells per the 2017 Korean braille rules (abbreviations, number and Roman-letter signs, punctuation) or uncontracted English, explaining every cell.

Encodes and decodes Caesar, ROT13, Atbash, Vigenère and rail-fence ciphers, with a brute-force view.

Composes one day’s reading for a zodiac animal or star sign from the day’s own 일진 and the traditional temperament of the sign. Seeded from the date, so it is the same all day and refreshing does not reroll it.

Draws one, three or five of the 24 staves and gives each its name, its sound, what the word means, and the Anglo-Saxon Rune Poem stanza in Old English with a translation. It deliberately does not print a divinatory meaning: those are 20th-century inventions under copyright, and no medieval source gives one.

Searches emoji, kaomoji and special characters by Korean or English name and copies them with one click.

Rebuilds a picture out of emoji chosen by mean colour, with the colour table measured in this browser’s own emoji font rather than shipped, and KakaoTalk and Discord sized presets.

Puts a character on your face through the webcam and drives it with your own blinks, head turns and mouth, entirely on your machine.

You place the landmarks on your own photo — eye corners, nose base, mouth corners, chin, hairline, jaw. It then measures 삼정, the five-eye-widths rule, jaw angle and philtrum ratio exactly, and gives each ratio its traditional 마의상법 reading.

Maps plain text onto Unicode look-alike alphabets — bold, script, circled, upside-down and wide.

Our own forced-choice questionnaire on the four public dichotomies — 24 items or an 8-item short form — scored as a strength bar per axis rather than a hard four-letter verdict.

Draws 한글, 漢字, かな or any other script as a large character banner by rasterising the system font and thresholding it, rather than looking glyphs up in a table.

Throws six lines by simulating the ritual itself: fifty yarrow stalks divided three times per line, or three coins. The two give different odds — a changing yang is three times as likely as a changing yin with stalks, equally likely with coins — and the page prints which you used and the arithmetic of every line. The Chinese text sits beside the translation.

Converts a picture into ASCII or ANSI-coloured characters at a chosen width and character set.

Converts any date to the three Maya counts using the Goodman–Martínez–Thompson correlation, and shows the arithmetic that makes them turn: 260 days from thirteen numbers and twenty names, a 365-day year with no leap day, and a base-20 tally with one base-18 digit.

Generates a maze at any size with a chosen algorithm, exported with or without the solution path.

Reads a line in one language by that language’s spelling rules, nativises it onto another language’s sound system, and ranks the phrases in that language that sound closest — rule-based, offline, with the alignment shown.

Converts text to and from Morse and can play it as audible tones at a chosen speed.

Generates project names, usernames and Korean nicknames from word lists, with availability-friendly patterns.

Computes a birth chart from VSOP87 for the planets, ELP 2000-82B for the Moon and this site’s own solar-longitude solver for the Sun — checked against JPL Horizons to a few arcseconds — then divides it by Placidus, whole sign or equal houses and lists the aspects with their exact separations.

Works out the two nine-star numbers from a birth date with every step shown: the digit sum, the subtraction from eleven, the 立春 and 節入り instants to the minute, and the 洛書 magic square shifted into a year plate. It prints no personality reading and no lucky direction, and says at length why not.

Scores a name under both letter tables and works a life path from a birth date by both of the usual methods, printing every step. A Korean name gets its own panel: neither table has a value for 김, so the number depends on which romanisation you pick, and the tool shows the common spellings side by side.

You trace 생명선, 감정선 and 두뇌선 over your own palm photo with a few drags. Length relative to the palm, curvature, forks and breaks are then measured exactly from the polyline, each with its traditional reading.

Spells a word out in the NATO alphabet or the Korean phone-spelling convention for reading aloud.

Draws on a pixel grid with pencil, fill, eraser, eyedropper, palette and mirror symmetry, imports a photo quantised into the grid, and exports PNG at an integer scale or SVG.

Draws numbers from a range with or without repeats, rolls dice notation and flips coins.

Picks one or several entries from a pasted list, with weights and an optional spinning wheel.

Assigns gift pairs without repeats or mutual matches, then keeps every name covered until it is tapped, so the draw can be run on one shared screen.

Generates sudoku puzzles at a chosen difficulty with a guaranteed unique solution, printable as PDF.

Shuffles a full 78-card deck with the browser’s CSPRNG and lays a one-card, three-card, Celtic Cross, horseshoe or two-person spread, each position labelled with what it traditionally answers. Meanings are quoted from Waite’s 1911 handbook; the card of the day is seeded from your name and the date, so it does not change when you reload.

Splits a list of names into balanced teams by count or size, and can keep or separate given pairs.

Renders any monospaced text art as a PNG or SVG with a chosen font, cell size, colour, background and optional transparency, so it survives being posted where monospace is not preserved.

Drags images or labels into S–F rows and exports the finished board as an image.

Measures typing speed and accuracy in Korean or English, in words or characters per minute.

Lays frequent words out by size in a shape or mask, with Korean tokenising and a stopword list.

Two birth dates give two animal signs and two day stems. Reports the exact relation between them — 삼합, 육합, 충, 원진, 형, 파, 해 — and the five-element relation of the day stems, each with the traditional verdict.

Prints the 六曜 of any date from the arithmetic that produces it — (lunar month + lunar day) mod 6 — with the old-calendar date beside it and the month laid out so you can see where the cycle skips, which is the only trace the Gregorian calendar keeps of the lunar month underneath.