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Regex Tester

A regex tester lets you write a regular expression and immediately see what it matches in your sample text. It highlights every match, supports flags like global and case-insensitive, and lists capture groups — making it easy to build and debug patterns.

How to Use the Regex Tester

  1. Enter your regular expression pattern.
  2. Set flags such as g (global) or i (case-insensitive).
  3. Type or paste the text to test against.
  4. See matches highlighted and listed with their capture groups.

Frequently Asked Questions

Which regex flavour does it use?

It uses JavaScript's built-in regular-expression engine, so patterns behave exactly as they would in JavaScript code.

Does it show capture groups?

Yes. For each match, the tool lists the full match and any captured groups, which helps when extracting parts of a string.

What do the flags mean?

g matches all occurrences, i ignores case, m treats each line separately for ^ and $, and s lets the dot match newlines.

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