Regex Tester - Online Regular Expression Test Tool
Free online regex tester with real-time matching, syntax highlighting, and capture groups. Test and debug regular expressions instantly in your browser.
Regular Expression
Common flags: g (global), i (case-insensitive), m (multiline)
Test Text
Regular Expression
What is Regex Tester?
A regular expression (regex) is a pattern-matching language used to search, match, and manipulate text. Regex patterns are widely used in programming for input validation, text extraction, search-and-replace operations, and data parsing across languages like JavaScript, Python, Java, and more.
How to Test Regex Patterns
- 1Enter your regex pattern in the pattern field (e.g., \b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.\|[A-Za-z]{2,}\b).
- 2Enter the test text you want to match against.
- 3Matches are highlighted in real-time. Use flags (/g, /i, /m) to control behavior.
Frequently Asked Questions
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