Regex Named Group Converter

Convert between named and numbered regex capture groups

Modern JavaScript and PCRE-style engines support named captures such as (?<year>\d{4}) and replacement tokens like $<year>. Older snippets still use numbered groups (\d{4}) and $1. This converter rewrites patterns and replacement strings in both directions so you can port expressions between codebases or documentation examples.

How to use this tool

1. Select Named groups to numbered or Numbered groups to named.
2. Paste the pattern and replacement string.
3. When converting to named groups, list capture names in order separated by commas.
4. Copy the converted pattern and replacement from the output fields.

Complex patterns with nested groups or lookaround may need manual review after conversion. Test results with the Regex Tester.