Helpmate tablebases Every solution to every position, precomputed.

← all materials

KBNvkq

5 pieces.

h#8.5
longest mate: h#7.5
deepest unique: 1
positions at that depth: h#7.5
deepest dual: h#6.5
deepest strict dual: 149,899,615
positions with a helpmate: 1,979,089
with a unique solution: 121,110,528
cells in the plane: 91,235,989 bytes
on disk

Deepest unique problems

Only one position exists at this depth.

h#7.5

1N6/7k/8/B7/8/1q6/8/1K6 w - - 0 1

Ka1 Kg6 Nc6 Kf5 Nd4+ Ke4 Nxb3 Kd3 Ka2 Kc2 Ka3 Kb1 Nd2+ Ka1 Bc3#

mirror single-piece single-piece:black

Note: the side to move is in check in the diagram.

Deepest dual problems

Deepest dual with different first and last moves: h#6.5. The deepest dual overall is h#7.5, where the two solutions share a first or a last move.

h#6.5

8/7k/5q2/8/8/8/N7/K4B2 w - - 0 1

Two solutions, with different first and last moves (2 starts, 2 ends).

Kb1 Kg6 Nc1 Kf5 Nb3 Ke4 Bg2+ Kd3 Ka2 Kc2 Ka3 Kb1 Be4#
Nc3 Kg6 Ka2 Kf5 Ne2 Ke4 Ka3 Kd3 Nc1+ Kc2 Nb3 Kb1 Bd3#

pure model mirror single-piece single-piece:black nocapture

Note: the side to move is in check in the diagram.

h#6.5

6k1/8/8/8/8/8/2K3B1/N3q3 w - - 0 1

Two solutions, with different first and last moves (2 starts, 2 ends).

Kb2 Kf7 Nc2 Ke6 Bh3+ Kd5 Nxe1 Kc4 Kc1 Kb3 Nc2 Ka2 Be6#
Nb3 Kf7 Nd2 Ke6 Nf3 Kd5 Nxe1+ Kc4 Kc1 Kb3 Nc2 Ka2 Bd5#

pure model ideal mirror switchback single-piece single-piece:black

h#6.5

8/7k/8/1N6/8/8/6q1/K6B w - - 0 1

Two solutions, with different first and last moves (2 starts, 2 ends).

Nd4 Kg6 Nb3 Kf5 Kb1 Ke4 Bxg2+ Kd3 Ka2 Kc2 Ka3 Kb1 Be4#
Bxg2 Kg6 Ka2 Kf5 Bh3+ Ke4 Nd4 Kd3 Nb3 Kc2 Ka3 Kb1 Bf5#

pure model ideal mirror single-piece single-piece:black