Regex Roulette · #11 · 2026-04-15
Match strings containing the word "cat" as a whole word
Difficulty 2/3
How to play
Write a regex that matches all green strings and rejects all red strings. Live feedback shows which strings pass. Shorter patterns score better.
Must match
- the cat sat — not yet evaluated
- cat — not yet evaluated
- a cat! — not yet evaluated
Must not match
- category — not yet evaluated
- concatenate — not yet evaluated
- scatter — not yet evaluated
- catalog — not yet evaluated
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Pattern body only — slashes and flags (e.g. /g, /i) aren't part of the input.
0/200 chars
Type a regex that matches all green strings and rejects all red strings · Back to hub