PNG Compressor
Quantises the palette and rewrites the deflate stream to shrink a PNG without changing its dimensions.
A PNG straight out of a design tool is usually two to five times larger than it needs to be, because it stores every colour it can rather than every colour it uses. This rewrites it with a smaller palette and a better-packed compression stream, at the same dimensions.
Reduces to a palette. Typically 60-80% smaller, and the usual reason a PNG is huge.
The default. A second or two per image.
Drop images here
PNG, JPEG, WebP or GIF. They are read in this tab and never uploaded.
How to use it
Drop the file in
PNG, JPEG, WebP and GIF are all accepted; the result is always a PNG. Several files at once is fine.
Check the quality figure
SSIM is shown next to the saving. Above 0.98 the difference is invisible at normal viewing size; below 0.95 look at the preview before you keep it.
Download, or send it on
The result can go straight into the resizer or the WebP converter without decoding twice.
Common questions
Is the file uploaded anywhere?
No. The codec runs in your browser, in a worker. Nothing leaves the tab, which is also why it works offline once the page has loaded.
Why is my photograph barely smaller?
Palette reduction works on flat colour — screenshots, logos, illustrations. A photograph has tens of thousands of distinct colours and little to gain; convert it to JPEG or WebP instead.
Does it keep transparency?
Yes, including partial alpha. The alpha channel is quantised along with the colours, so a soft shadow stays soft.
Feed it from
WebP Converter
Converts images to or from WebP, with a quality slider and lossless mode.
AVIF Converter
Converts images to or from AVIF and reports the size against the JPEG or WebP equivalent.
Image Format Converter
Converts between PNG, JPEG, WebP, AVIF, GIF, BMP and TIFF, one file or a whole folder at a time.
Image Resizer
Resizes by pixels, percentage or a target longest edge, with aspect-ratio lock and batch presets.
Next
These accept what this tool produces, so the result can go straight in.
EXIF Remover
Strips camera, GPS and editing metadata from photos while leaving the pixels untouched.
Image Resizer
Resizes by pixels, percentage or a target longest edge, with aspect-ratio lock and batch presets.
Image to Base64 / Data URI
Encodes an image as a Base64 string or a ready-to-paste data URI for CSS, HTML or JSON.
WebP Converter
Converts images to or from WebP, with a quality slider and lossless mode.
Background Remover
Keys out a flat or single-colour background in OKLab and returns a transparent PNG, with a brush for fixing the edges.
Favicon Generator
Produces the whole favicon set — ICO, PNGs, Apple touch icon, web manifest — plus the HTML to paste.