Regex Tester

Test regular expressions with live matches, capture groups, and replace — 100% in your browser.

100% In-Browser & Private — your data never leaves this device

PeachTools Pro

Batch processing, unlimited files, ad-free.

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How to use the Regex Tester

  1. Enter a pattern and toggle flags (g, i, m, s, u, y).
  2. Paste the text you want to search.
  3. Optionally set a replace string (supports $1 groups).
  4. Review matches and the replace result locally.

FAQ

Is my text uploaded?
No. Matching runs with JavaScript RegExp in your browser.
Which flavor of regex is this?
Your browser’s JavaScript regular expression engine (ECMAScript).

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