Can I use capture groups in the replacement?

Yes. Reference captured groups with $1, $2, etc. in the replacement string. Use $& to insert the entire matched substring.

Does the global flag replace all matches?

Yes. With the g flag every occurrence is replaced. Without it, only the first match is replaced.

Can I replace with an empty string to delete matches?

Yes. Leave the replacement field blank to delete every match.

Regex replace

Use a regular expression to find patterns in your text and replace them with a substitution string. Supports capture group references like $1, $2 in the replacement.

Test string

REPLACE WITH

Result

Enter a pattern and test string above

MODE

Runs entirely in your browser

How it works

The tool uses the browser's native JavaScript RegExp engine. Patterns are compiled with new RegExp(pattern, flags) and results are computed synchronously. Invalid patterns show an error badge, they never crash the page.

Processing runs in your browser

Both the pattern and the test string are processed entirely in your browser. Our servers are not involved at any point.

Related operations

For plain substring swaps without regex, try find and replace. To validate JSON patterns you are matching, use the JSON formatter. For decoding escape sequences in HTML attribute values, see HTML entities.

Frequently asked questions

Can I use capture groups in the replacement?: Yes. Reference captured groups with $1, $2, etc. in the replacement string. Use $& to insert the entire matched substring.
Does the global flag replace all matches?: Yes. With the g flag every occurrence is replaced. Without it, only the first match is replaced.
Can I replace with an empty string to delete matches?: Yes. Leave the replacement field blank to delete every match.

Regex replace

How it works

Processing runs in your browser

Related operations

Frequently asked questions

Related tools