Developer Tools
Regex Explainer
Break a regular expression down into a readable, indented tree.
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About this tool
Paste any ECMAScript regex and see a token-by-token explanation — character classes, quantifiers, capturing/non-capturing groups, lookarounds, alternation, anchors, and shorthand classes — with proper nesting under groups.
Frequently asked questions
Which features are supported?
Capturing/non-capturing/named groups, lookahead and lookbehind (positive and negative), character classes, quantifiers (greedy and lazy), shorthand classes (\d, \w, \s and friends), anchors, escapes, and alternation.
Will this catch syntax errors?
Use the Regex Tester for compilation errors — the explainer is forgiving and surfaces tokens even when the regex doesn't compile.