Developer Tools
Regex Tester
Test regular expressions with flags, matches, and capture groups.
Last validated: 2026-02-14
Regex Tester lets you execute regular expressions against sample text and inspect matches with exact positions and capture groups. It is useful for parser development, input validation, and troubleshooting production patterns before shipping changes. You can toggle common flags (`i`, `m`, `x`) to validate behavior under different matching modes. The tool surfaces compile errors immediately and lists each match boundary, which helps debug greedy patterns and group logic. Use it to harden patterns safely before embedding them in application code.