Why are no matches returned?

Check your pattern and flags. Case-sensitive matching without i flag is common.

What does global flag do?

With g, all matches are returned. Without g, only first match is shown.

It uses JavaScript RegExp engine semantics.

Developer Tools

Write regex and test it live against sample text with flags and match positions.

Regex Pattern

Flags

Test Text

Total MatchesiTotal number of matches found by your regex pattern.Copy

Used FlagsCopy

Regex StatusCopy

Invalid Regex

Regex ErrorCopy

Pattern is empty.

Raw JSON (technical)

{
  "valid": false,
  "error": "Pattern is empty.",
  "flags": "g",
  "totalMatches": 0,
  "matches": []
}

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