Which regex flavour is used?

JavaScript RegExp — the same engine used in Node.js and all modern browsers.

Are all matches found?

Yes. The global flag (g) is always applied, so all non-overlapping matches are returned.

What do the flags do?

i = case insensitive, m = ^ and $ match line boundaries, s = dot matches newline characters.

Is my text sent anywhere?

No. Everything runs in your browser.

Developer Tools

Regex Tester — Test Regular Expressions in Browser, No Upload

🔒 Runs in your browser

Test JavaScript regular expressions against any input with live match highlighting. Supports i, m, and s flags. Runs entirely in your browser — no upload, no server, no tracking.

How to use this tool

Enter your regular expression in the pattern field.
Paste the text to test against.
Review highlighted matches and captured groups.

Regular expression

Test string

Frequently Asked Questions

Which regex flavour is used?: JavaScript RegExp — the same engine used in Node.js and all modern browsers.
Are all matches found?: Yes. The global flag (g) is always applied, so all non-overlapping matches are returned.
What do the flags do?: i = case insensitive, m = ^ and $ match line boundaries, s = dot matches newline characters.
Is my text sent anywhere?: No. Everything runs in your browser.

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