4x4 Chess


4x4 chess is similar to chess, except the board is smaller, there is no castling, no double pawn step, and pawns are allowed on the first rank (fourth for black). Starting position is not defined. 4x4 chess has 3.68 quadrillion unique legal positions (a 16-digit number), 22 thousand times more than 3x4 chess. All positions with up to 9 pieces are already solved, and further solving is being planned. The deepest win found to date is 59 moves long (example on the right).


September 5, 2011
All 9-piece positions are solved in DTM metric.
June 28, 2011
There are 3,677,542,994,054,890 unique legal positions in 4x4 chess (details).
June 1, 2011
3-to-8-piece databases are complete in 4 metrics (DTM, DTC, DTZ, WDL) and can be queried in the web-interface. The initial 4x4 chess homepage created.


  © 2011 Kirill Kryukov
Available under the CC BY 3.0 License