Line Numbering
Adds or removes leading line numbers with a start value, step, padding and separator.
Adds numbering to a list of lines, or takes existing numbering off. The removal is the harder half and the one worth having: it only strips leading numbers that form an increasing run, so a column of years or amounts is left alone.
Text
Numbering
What goes between the number and the line.
Result
How to use it
Choose add or remove
Removing tells you how many lines it found numbering on and how confident it is, so you can see whether it read your data as a list.
Set the start, step and separator
A separator of ". " gives 1. text; ") " gives 1) text; a tab gives something a spreadsheet will split into two columns.
Pad when the numbers must line up
01, 02 … 11 keeps the text starting at the same column in a monospaced view, which matters for anything you are going to read in a terminal or diff.
Common questions
It refused to remove my numbers
The leading numbers do not increase, so they look like content — a column of years, prices or IDs. Refusing is the safe behaviour: deleting the first field of a data file is much worse than leaving a numbered list numbered.
What happens to blank lines?
With "skip blank lines" on they stay blank and do not consume a number, so the numbering counts items rather than lines. Turn it off to number every line including the empty ones.
Can I number from something other than 1?
Yes — set the start, and the step too. A step of 10 gives 10, 20, 30, which is the old BASIC convention for leaving room to insert lines later.
Feed it from
Case Converter
Converts between UPPER, lower, Title, Sentence, camelCase, snake_case, kebab-case and CONSTANT_CASE.
Text Diff
Compares two texts side by side or inline, at line, word or character granularity.
Duplicate Line Remover
Removes duplicate lines, keeps only duplicates, or counts how many times each line appeared.
Line Sorter & Shuffler
Sorts lines alphabetically, numerically, by length or randomly, with reverse and case options.
Next
These accept what this tool produces, so the result can go straight in.
ASCII Table Generator
Renders a table as monospaced ASCII, Markdown or box-drawing borders for READMEs and comments.
List Formatter
Turns lines into a comma list, quoted SQL IN clause, JSON array or bullet list, and back again.
Line Sorter & Shuffler
Sorts lines alphabetically, numerically, by length or randomly, with reverse and case options.
Find & Replace
Replaces text by literal, whole word or regular expression, with capture groups and a preview of every hit.
Markdown Editor
Edits Markdown with a live preview and exports the rendered HTML, with GFM tables and task lists.
Text Anonymiser
Finds emails, phone numbers, card numbers and IDs in free text and masks or pseudonymises them.