Regex Match Lab

Keep your regex pattern and its examples together. See matched text, numbered capture groups and source ranges as you edit. Preview replacements before using them elsewhere. Start with Email parts, Log levels or ISO dates, or enter your own pattern and sample. Check edge cases in Test cases. Set each example to Should match or Should not match, then choose Run all. The check looks for a match anywhere in each example. Use \A…\z when you need to check the whole text. Save the pattern, sample, replacement, flags and examples as one test on your device. Reopen it whenever you need to check the same inputs again. From Saved tests, choose Back up saved tests to export a JSON file. Use Restore from JSON and Add copies to bring tests back without replacing existing saved tests. Matching and saved tests work locally, with no account or automatic sync. You choose when to export or share. Large inputs and result counts are limited.