Regex Tester

Test regex patterns live with match highlighting and capture groups.

Match results

0 matches
Enter a pattern and test string to see the result.
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Reference capture groups as $1, $2, and so on.

About this tool

Regex Tester matches patterns against sample text in real time for validation and parsing.

Greedy .* often swallows too much when extracting order IDs from logs. Lock the pattern on one sample line, then add failure cases (spaces, empties) before production.

Tip — Greedy .* can over-match — try narrower groups or non-greedy patterns.

How to use

  1. 1Enter code, JSON, regex, or other input.
  2. 2Run format, validate, or test actions.
  3. 3Review and copy the output.

FAQ

What do g/i/m flags do?

g = global, i = case-insensitive, m = multiline ^$. Combine as needed.

Empty capture groups?

The group did not match or the pattern failed—simplify and widen step by step.

Can I test replace?

Use the replace field if present; otherwise verify matches here and replace in your editor.

Are files uploaded to a server?

No. Every tool runs entirely in your browser. Files and text you enter are never sent to our servers.