Regex Tester
Test a regular expression against sample text, inspect matches and capture groups, and see where each match lands. Evaluation runs in a worker with a time limit.
Runs in your browser
No account. No upload.
Workspace
LOCAL
g · worker time limit 1.5s
Pattern
The pattern runs against the test text below. No JavaScript is evaluated.
Test text
Long or expensive patterns are stopped by the worker so the page stays responsive.
Highlighted matches
Matches & capture groups
Enter a pattern to see matches and capture groups.
How to use
- 1Enter a pattern and choose the flags you need.
- 2Paste or type test text into the panel.
- 3Review the highlighted matches, match count, and capture groups.
Examples
Find identifiers
Match request IDs, order numbers, or other fixed-shape identifiers in logs.
Validate dates
Test an ISO date pattern against values from an API or form.
Extract log fields
Use capture groups to pull a level, timestamp, and message apart.
Privacy
Patterns and test text run in a browser worker with a time limit. Nothing is uploaded, logged, or stored.
Do not paste secrets or production credentials into any browser tool.
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