Basic chess endgames

This page shows the analysis of all pawnless four piece chess endgames. Before looking at these details it's probably best to first read the friendly introduction.

How to read the results table

Firstly, the entire table is from the perspective of White winning. The Pieces column shows the pieces on the board: first White's pieces, then an underscore character _, then Black's pieces. The standard notation for pieces is used: k for King, q for Queen, r for Rook, b for Bishop and n for Knight. Next the table is divided up into positions where it is White to move and positions where it is Black to move. In each division the max column shows the number of White moves to achieve checkmate in the longest win, the %win column shows the percentage of legal positions that are winning for White, the #win column shows the number of legal positions that are winning for White, and the #legal column shows the number of legal positions.

Results table

 Pieces  | White to move                    | Black to move 
---------+----------------------------------+----------------------------------
         | max | %win |     #win |   #legal | max | %win |     #win |   #legal
         |-----+------+----------+----------+-----+------+----------+----------
 k_k     | --- |  --- |        0 |     3612 | --- |  --- |        0 |     3612
 k_kb    | --- |  --- |        0 |   223944 | --- |  --- |        0 |   193284
 k_kbb   | --- |  --- |        0 | 13660584 | --- |  --- |        0 | 10164056
 k_kbn   | --- |  --- |        0 | 13660584 | --- |  --- |        0 | 10875504
 k_kn    | --- |  --- |        0 |   223944 | --- |  --- |        0 |   205496
 k_knn   | --- |  --- |        0 | 13660584 | --- |  --- |        0 | 11499304
 k_kq    | --- |  --- |        0 |   223944 | --- |  --- |        0 |   144508
 k_kqb   | --- |  --- |        0 | 13660584 | --- |  --- |        0 |  7698432
 k_kqn   | --- |  --- |        0 | 13660584 | --- |  --- |        0 |  8245296
 k_kqq   | --- |  --- |        0 | 13660584 | --- |  --- |        0 |  5657120
 k_kqr   | --- |  --- |        0 | 13660584 | --- |  --- |        0 |  6911296
 k_kr    | --- |  --- |        0 |   223944 | --- |  --- |        0 |   175168
 k_krb   | --- |  --- |        0 | 13660584 | --- |  --- |        0 |  9366840
 k_krn   | --- |  --- |        0 | 13660584 | --- |  --- |        0 |  9905048
 k_krr   | --- |  --- |        0 | 13660584 | --- |  --- |        0 |  8325184
 kb_k    | --- |  --- |        0 |   193284 | --- |  --- |        0 |   223944
 kb_kb   |   1 |   0% |      416 | 11832464 |   0 |   0% |      112 | 11832464
 kb_kn   |   1 |   0% |       16 | 11832464 |   0 |   0% |        8 | 12535256
 kb_kq   | --- |  --- |        0 | 11832464 | --- |  --- |        0 |  8952608
 kb_kr   | --- |  --- |        0 | 11832464 | --- |  --- |        0 | 10780728
 kbb_k   |  19 |  49% |  5007216 | 10164056 |  19 |  41% |  5628080 | 13660584
 kbn_k   |  33 | 100% | 10822184 | 10875504 |  33 |  82% | 11188168 | 13660584
 kn_k    | --- |  --- |        0 |   205496 | --- |  --- |        0 |   223944
 kn_kb   |   1 |   0% |       40 | 12535256 |   0 |   0% |        8 | 11832464
 kn_kn   |   1 |   0% |       40 | 12535256 |   0 |   0% |        8 | 12535256
 kn_kq   | --- |  --- |        0 | 12535256 | --- |  --- |        0 |  8952608
 kn_kr   |   1 |   0% |       32 | 12535256 |   0 |   0% |        8 | 10780728
 knn_k   |   1 |   0% |     1232 | 11499304 |   0 |   0% |      240 | 13660584
 kq_k    |  10 |  ALL |   144508 |   144508 |  10 |  90% |   200896 |   223944
 kq_kb   |  17 | 100% |  8925252 |  8952608 |  17 |  77% |  9097332 | 11832464
 kq_kn   |  21 |  99% |  8894128 |  8952608 |  21 |  80% | 10088688 | 12535256
 kq_kq   |  13 |  42% |  3737092 |  8952608 |  12 |   0% |    40628 |  8952608
 kq_kr   |  35 |  99% |  8863768 |  8952608 |  35 |  66% |  7062680 | 10780728
 kqb_k   |   8 |  ALL |  7698432 |  7698432 |  10 |  91% | 12379568 | 13660584
 kqn_k   |   9 |  ALL |  8245296 |  8245296 |  10 |  90% | 12343856 | 13660584
 kqq_k   |   4 |  ALL |  5657120 |  5657120 |  10 |  98% | 13378232 | 13660584
 kqr_k   |   6 |  ALL |  6911296 |  6911296 |  16 |  99% | 13519192 | 13660584
 kr_k    |  16 |  ALL |   175168 |   175168 |  16 |  90% |   201700 |   223944
 kr_kb   |  29 |  35% |  3787160 | 10780728 |  29 |   3% |   381888 | 11832464
 kr_kn   |  40 |  48% |  5210920 | 10780728 |  40 |  11% |  1364800 | 12535256
 kr_kq   |  19 |  29% |  3090088 | 10780728 |  18 |   0% |    17136 |  8952608
 kr_kr   |  19 |  29% |  3139232 | 10780728 |  19 |   1% |    72464 | 10780728
 krb_k   |  16 |  ALL |  9366840 |  9366840 |  16 |  91% | 12458920 | 13660584
 krn_k   |  16 |  ALL |  9905048 |  9905048 |  16 |  91% | 12406892 | 13660584
 krr_k   |   7 |  ALL |  8325184 |  8325184 |  16 | 100% | 13621424 | 13660584
---------+-----+------+----------+----------+-----+------+----------+----------
 Summary |  40 |  29% |  1.179E8 |  4.033E8 |  40 |  34% |  1.355E8 |  4.033E8


An endgame analysis by Joe Leslie-Hurd on 8 February 2005.