Regex101
The best regex debugger on the web. Real-time explanation, match highlighting, test strings, and a library of saved patterns. Supports PCRE2, JavaScript, Python, Golang regex. It explains each token in plain language beside the pattern, which turns debugging into reading rather than guessing.
Not sure how to add Regex101 to your home screen? Step-by-step for Chrome, Safari, Firefox and Edge — it takes about ten seconds, and there is no app store involved.
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