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Regex Tester

Test regular expressions with real-time match highlighting

Regular Expression

Test String

Highlighted Matches

Matches will be highlighted here...
No matches yet

Common Patterns

How Regex Testing Works

Regular expressions (regex) are patterns used to match character combinations in strings. This tool lets you test your regex patterns in real-time with instant visual feedback.

Features

Frequently Asked Questions

What are regex flags?
Flags modify pattern matching: g (global), i (case-insensitive), m (multiline), s (dotAll - dot matches newlines), u (unicode support).
What are capture groups?
Capture groups are portions enclosed in parentheses () that capture matched text for back-references. For example, (\\d+)-(\\d+) captures two digit groups.
How do I test my regex?
Enter your pattern, select flags, and type your test string. Matches are highlighted in real-time with details shown below.

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