正規表現テスター
JavaScript 正規表現のライブテスト — フラグ、グループ、位置
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正規表現テスター
Build and debug JavaScript regular expressions interactively. See every match, capture group and named group, with positions highlighted in the input. Supports flags g i m s u y. A multilingual alternative to regex101.
- JavaScript regex engine (ECMAScript)
- Flags: g i m s u y
- All matches highlighted in context
- Numbered and named capture groups
- Match positions and lengths
- Privacy: pattern and text stay local
FAQ
Which regex flavor is supported?
JavaScript / ECMAScript regex. This differs from PCRE (Perl) in look-around and named groups syntax. For server-side patterns, double-check on your server runtime.
Why is the g flag forced on?
The tester always finds all matches. matchAll with g is the cleanest way to enumerate them without lastIndex pitfalls.