docsntools

Regex Tester

JS-flavour regex with flag toggles, capture groups, and live highlights.

100% in your browser · no uploads · no ad trackers

About Regex Tester

Regex Tester runs JavaScript-flavour regular expressions against any input with live match highlighting and capture-group breakdowns. Use it to iterate on a pattern, debug why something isn't matching, or extract data from log lines without writing a script.

Pattern

//g

Test string (0 matches)

Replace preview

-

Match table

No matches.

How to use

  1. 1.Type your regex and flags.
  2. 2.Paste input text.
  3. 3.See matches highlighted.

FAQ

Which regex flavour is supported?
JavaScript regex - the same engine used by Node.js and browsers. PCRE-only features like recursion or possessive quantifiers aren't available.
Are capture groups shown?
Yes - each match lists its captured groups (numbered and named) so you can verify your extraction logic.
Which flags can I toggle?
All standard JS flags: `g`, `i`, `m`, `s`, `u`, and `y`.
Is Regex Tester free?
Yes. Every tool on docsntools is 100% free with no signup, no watermarks, and no upload limits.
Are my files uploaded to a server?
No. All processing happens entirely in your browser. Your files never leave your device.
Does it work on mobile?
Yes - every tool is responsive and works in modern mobile browsers (Chrome, Safari, Firefox).

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