Regex Tester
FeaturedBuild, debug, and test JavaScript regular expressions live with match highlighting and group capture breakdown.
- 1hello@example.com
- 2bob@test.org
About the Regex Tester
A live Regular Expression tester designed for developers. Build complex patterns with real-time match highlighting, group capture breakdown, and error detection. Supports standard JavaScript regex syntax and flags.
How to use the Regex Tester
- 1Enter your regex pattern (e.g. \b[A-Z]+\b).
- 2Add any necessary flags (g, i, m).
- 3Type or paste your test string into the editor.
- 4Review the match list and captured groups in the panels below.
Why people use it
- Validate email, phone number, or URL patterns.
- Extract specific data from unstructured text blocks.
- Test search-and-replace patterns before using them in code.
- Learn regular expression syntax with instant feedback.
Frequently asked questions
Which regex engine does this use?
This tool uses the native JavaScript RegExp engine in your browser, ensuring 100% compatibility with your web projects.
What do the flags mean?
Flags like 'g' (global) find all matches, 'i' (ignore case) makes it case-insensitive, and 'm' (multiline) affects start/end anchors.
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