Regex Tester

Free regex tester. Test regular expressions against text with live match highlighting and flag support.

How the Regex Tester works

The tester compiles your pattern into a JavaScript RegExp object with the selected flags (g for global, i for case-insensitive, m for multiline, s for dotall). It then executes the regex against your test text, collects all matches with their positions, and highlights them in the output.

How to use the Regex Tester

  1. 1The regex tester is designed to be simple and fast.
  2. 2Enter your regex pattern.
  3. 3Set flags (g, i, m).
  4. 4Enter test text.
  5. 5See matches and positions.
  6. 6Your result is shown immediately.

Examples

  • \d+ matches all numbers in text
  • Supports g, i, m, s flags

Benefits

  • Completely free with no signup required.
  • Runs entirely in your browser for instant results and privacy.
  • Works on mobile, tablet and desktop.
  • Results can be copied with one click.

Frequently Asked Questions

Is the regex tester free to use?

Yes. The regex tester is 100% free, with no signup, no watermark and no hidden limits.

Does the regex tester store my data?

No. All calculations and processing happen locally in your browser. Nothing is uploaded to a server.

Does the regex tester work on mobile?

Yes. The regex tester is fully responsive and works on phones, tablets and desktop computers.

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