Add Line Numbers

What this tool does

Add Line Numbers takes whatever text you paste in and puts a running number in front of every line. It's handy for turning a plain list into a ranked one, referencing specific rows in code or a transcript, prepping steps for a recipe or manual, or just making a long block of text easier to talk about ("look at line 42"). Everything runs in your browser, so your text is never uploaded to a server.

The options, explained

Four small controls change how the numbers look. Start number sets where counting begins — use 0 for a zero-indexed list or any value you like. Separator is the text placed between the number and your line; the default is a dot and a space ("1. "), but you can use a tab, a parenthesis like ") ", a colon, or nothing at all. Zero-pad width lines everything up by padding numbers with leading zeros, so a width of 3 turns 7 into 007 — great for filenames and sortable lists. Skip blank lines leaves empty lines untouched and doesn't spend a number on them, so paragraph breaks stay clean.

How to use it

1. Paste or type your text into the top box, one item per line.
2. Set the start number (1 by default).
3. Type the separator you want after each number.
4. Optionally set a zero-pad width and tick Skip blank lines.
5. Watch the numbered output update instantly, then press Copy result.

FAQ

Does my text get uploaded anywhere?

No. All numbering happens locally in your browser with JavaScript. Nothing is sent to a server.

Can I start numbering from 0 or another value?

Yes. Set the start number to any whole number, positive or negative, and counting begins there.

How does "skip blank lines" work?

Empty or whitespace-only lines are kept in place but not given a number, so the count only advances on real content.

What is zero-padding for?

It adds leading zeros so numbers share the same width (01, 02 … 10). This keeps lists visually aligned and sortable.