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post/dev-utils/v1/regex_test1 credit

Test a regex against text: matches + groups + named groups, optional replace. User patterns run with a hard 1s timeout (ReDoS-guarded) + size caps.

Working example

Parameters

patternrequired

The regular expression (≤2000 chars; Python `regex` syntax — PCRE-compatible incl. \p{...}).

inputrequired

The subject text to scan.

flagsoptional

Flag letters, any of: i (ignorecase), m (multiline), s (dotall), x (verbose). E.g. 'im'.

replacementoptional

Optional replacement template — when set, `replaced` holds the substituted text (backrefs \1, \g<name>).

max_matchesoptional

Cap on returned matches. (1–500)

request preview

curl -X POST https://api.reefapi.com/dev-utils/v1/regex_test \
  -H "x-api-key: $REEF_KEY" \
  -H "content-type: application/json" \
  -d '{"pattern":"(\\w+)@([\\w.]+)","input":"mail [email protected] now"}'

Hit Send to run this endpoint live.