Regex Tester client-side ?
How to use Regex TesterThe regular expression tester lets you write a pattern and match it against sample text in real time. Matches are highlighted as you type, and capture groups are broken out to make debugging easier.
It is the ideal tool for validating an email format, extracting data from a log, or refining a pattern before you drop it into your code. Evaluation runs in your browser using the JavaScript regex engine, so your text and pattern stay private.
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The regular expression tester lets you write a pattern and match it against sample text in real time. Matches are highlighted as you type, and capture groups are broken out to make debugging easier. It is the ideal tool for validating an email format, extracting data from a log, or refining a pattern before you drop it into your code. Evaluation runs in your browser using the JavaScript regex engine, so your text and pattern stay private.
Test regular expressions with highlighted match visualization.
How to use Regex Tester
The regular expression tester lets you write a pattern and match it against sample text in real time. Matches are highlighted as you type, and capture groups are broken out to make debugging easier. It is the ideal tool for validating an email format, extracting data from a log, or refining a pattern before you drop it into your code. Evaluation runs in your browser using the JavaScript regex engine, so your text and pattern stay private.
Frequently asked questions
Which regex engine is used?
The tool uses the native JavaScript regex engine in your browser. The syntax is therefore JavaScript flavored, close to most languages but with a few specifics.
How do I enable options like case insensitive matching?
You can add the usual flags, for example i to ignore case, g for all matches, and m for multiline mode.
Can I see capture groups?
Yes, each match displays its numbered capture groups, which helps you confirm that your pattern extracts the right parts of the text.
Is my text sent to a server?
No, the test runs entirely in your browser. Neither the pattern nor the text is transmitted.