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Regex Tester
Build and debug regular expressions with live highlighting, flag toggles, capture groups, and an optional replace mode.
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\d digit · \D non-digit\w word char · \W non-word\s whitespace · \S non-ws. any (except \n) · [abc] char class^ start · $ end\b word boundary · \B non-boundary? 0–1 · * 0+ · + 1+{n} exactly n · {n,m} n–m(abc) group · (?:abc) non-capture(?<name>…) named · \1 backref(?=x) lookahead · (?!x) negativea|b alternation