DEV 📝 Text Utilities

Regular Expression Tester

Test and debug regular expressions against sample text. See all matches, their positions, and capture groups. Supports JavaScript regex syntax with flags for case insensitivity, global search, and multiline mode.

How to Use

  1. Enter or paste the text you want to test against.
  2. Type a regular expression pattern (without /delimiters/).
  3. Toggle flags: case insensitive, global, or multiline.
  4. Click Transform to find all matches.
  5. Review the matches, their positions, and any capture groups.

How It Works

The tool uses JavaScript's native RegExp engine. Each match reports the full match string, its starting index in the input, and any numbered capture groups. The global flag finds all matches; without it, only the first match is returned.
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