Regex Tester

Test JavaScript regular expressions and inspect matches, captures and positions.

Processed locally in your browser. Your input is not uploaded.

How to use Regex Tester

Enter a JavaScript pattern without slash delimiters. Choose global, case-insensitive, multiline, dotAll and Unicode flags. Results are shown as a safe plain-text list.

Details and limits

Match positions are zero-based UTF-16 offsets with an exclusive end. Results stop at 1,000 matches. A worker time limit reduces the risk from slow patterns; it does not guarantee that every expensive pattern can be evaluated. Text is limited to 100,000 characters.

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