Add Prefix Each Line
Paste plain text, enter a prefix, and add it locally to every non-blank line.
Add a prefix to each line
A QUICK WALKTHROUGH
How to use this tool
- Paste up to 50,000 characters of text.
- Enter a prefix of up to 200 characters.
- Add the prefix, then copy or download the plain-text result.
Literal line prefixing
The exact prefix is placed before every line containing a non-whitespace character. Empty and whitespace-only lines remain unchanged.
Local processing
Text is processed in your browser only. Input is limited to 50,000 characters, the prefix to 200 characters, and output to 500,000 characters.
GOOD TO KNOW
Common questions
Are blank lines changed?
No. Empty and whitespace-only lines remain exactly as entered.
Are line endings preserved?
Yes. LF, CRLF, and CR separators, including a trailing newline, are retained.
Is the prefix treated literally?
Yes. It is inserted as text and is never interpreted as a pattern or command.