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Data & DevRegex Tester
Test and debug JavaScript Regular Expressions in real time. Highlights matches, extracts numbered and named capture groups, and displays match start/end indices with timeout protection.
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How it works
- Enter your regex pattern and select flags (`g`, `i`, `m`, `s`, `u`).
- Type or paste test text into the input area.
- Matches and capture groups are computed and highlighted immediately.
Privacy & Processing Information
Tested locally in your browser. Catastrophic backtracking protection safeguards your tab.
No account, tracking, or file storage required.
Frequently Asked Questions
What do the regex flags mean?
`g` = global match (all occurrences), `i` = case insensitive, `m` = multiline anchor matching (`^` and `$`), `s` = dot matches newlines, `u` = full unicode support.
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