Prefix Lines
Add the same prefix before every line.
Add the same prefix before every line. Paste or type your text and the result updates instantly. Everything runs in your browser, so nothing is uploaded, nothing is stored, and there is no limit on how much text you can process.
What Prefix Lines does
The text you enter is added to the start of every line, including blank ones. It is the fastest way to turn a plain list into markdown bullets or to comment out a block of configuration.
Your text never leaves your device
This tool is written in JavaScript and runs locally in the browser tab. No text is transmitted to a server, none is written to a log, and none is retained after you close the page. That makes it safe for drafts, client work and anything else you would rather not paste into an online form.
Why results can differ from other tools
Text processing involves judgement calls: what counts as a word, whether a hyphenated compound is one token or two, how a line ending is treated. Different tools resolve these differently, so a small discrepancy between this and a word processor is expected rather than an error.
Worked example
Run on a short sample so you can see exactly what changes before pasting your own text:
| Input | Output |
|---|---|
| banana apple banana cherry |
- banana - apple - banana - cherry |
Frequently asked questions
Is Prefix Lines free to use?
Yes, completely. There is no account, no sign-up, no usage limit and no watermark. Every tool on this site runs in your browser and stays free.
Does my text get uploaded anywhere?
No. The processing happens locally in your browser using JavaScript. Your text is never transmitted to a server, never logged and never stored.