Test regular expressions online with live match highlights, capture group breakdown, and regex cheat sheets.
Test a JavaScript regular expression against sample text. Adjust flags, inspect matches and captured groups, or try a replacement string. The workspace uses your browser's regular-expression engine.
Step-by-Step Walkthrough
Step 1
Enter a pattern and the text you want to test.
Step 2
Set the flags and inspect match highlights or pattern errors.
Step 3
Try capture groups or replacement mode, then copy the pattern you need.
Pro Tip for Best Output Quality
Complex expressions or large text can slow the browser. A valid pattern can still be unsuitable for your data.
Key Capabilities & Features
Live matches
See which portions of the sample text match.
Pattern flags
Toggle the available JavaScript flags.
Capture groups
Inspect the groups returned by each match.
Replacement preview
Try a replacement pattern without changing the source text.
Recommended Creative Use Cases
Frequently Asked Questions
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