Gomoku · Renju
Gomoku
Play five-in-a-row against Rapfi, the strongest Gomoku engine in the world — running entirely in your browser. Freestyle, standard, and Renju rules with full forbidden-move adjudication, plus the Soosyrv-8 opening ceremony.
A world champion in the tab
Rapfi has won every Gomocup league it entered since 2024 — freestyle, standard, and Renju alike. Here it runs on WebAssembly, thinking at full strength on your device with nothing installed.
Every rule, enforced
Double threes, double fours, overlines — the Renju forbidden moves are adjudicated exactly, down to the recursive false-three cases. Prefer plain five-in-a-row? Freestyle and standard rules are one click away.
Learn by playing
A hands-on curriculum walks you from your first five to forced wins — open threes, fours, VCF sequences, forbidden-move traps, and real games against a tuned-down engine.