Regex Tester
Build, test, and debug regular expressions with real-time match highlighting. Free, no account needed.
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Enter a pattern and test string to start matching
Matches are highlighted in real time as you type
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Regex Testing: Write and Debug Regular Expressions Instantly
Regular expressions are powerful but tricky. Learn how to write, test, and debug regex patterns effectively.
What Is a Regular Expression?
A regular expression (regex or regexp) is a sequence of characters that defines a search pattern. They are used to search, match, extract, replace, and validate text. Regex patterns are supported natively in nearly every programming language and are essential tools in any developer's toolkit.
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