Regex Tester
Test regular expressions against sample text with live match and capture-group highlighting.
Type a regular expression and sample text, and see every match highlighted live, with capture groups broken out individually as you type. Useful for building a validation pattern, debugging why a regex isn't matching what you expect, or figuring out someone else's cryptic pattern before reusing it. Uses standard JavaScript regex syntax and flags (g, i, m, s), and evaluates entirely in your browser.
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Details
- Category
- Developer & data
- Runs
- In your browser
- Files uploaded
- No
- Cost per run
- Free
- Sign-in
- Not required
- Works offline
- Yes, once loaded
Last updated 2026-08-03
Common questions
Which regex flavor does this use?
Standard JavaScript regex syntax, since matching runs in your browser's own regex engine.
Can I test capture groups?
Yes - each capture group in a match is broken out and labeled separately in the results.
Which flags are supported?
Global (g), case-insensitive (i), multiline (m), and dotAll (s) flags can all be toggled.
Is my text uploaded anywhere?
No - matching happens entirely in your browser.