Regex Tester
Regex Tester runs your regular expression against sample text and highlights every match live, with flags and capture-group details.
🔒 Matching runs locally in your browser (JavaScript regex).
How to use Regex Tester
- Enter a regex pattern and flags.
- Paste your test text.
- See matches highlighted instantly.
Frequently asked questions
Which flavour of regex is this?
JavaScript regular expressions, with support for the g, i, m, s and u flags.
Does it show capture groups?
Yes — it lists matches and their captured groups.
Is my text uploaded?
No, matching runs entirely in your browser.
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