Skip to content
Paradigm

Lab

Draughts, learned from scratch

Two small neural networks started out rated below random play. They trained by self-play: 30 million games of draughts in 10 hours on one desktop computer, and a new version was kept only when it beat the one before it. Below is the recorded history of that run, and the networks themselves, running in your browser.

Recorded training history

How the networks got better

Run v1-2026-09-17, started 2026-09-17, commit 0a5c5a0. Every generation then played separately seeded games against fixed opponents: random moves, a greedy player, and minimax searches of depth 1 to 6, 134,800 arena games in all. Ratings are Elo on that ladder, with random moves at 0.

Self-play games
30,015,856
Training time
10 hours
Arena games
134,800
Elo rating of each promoted generation against training games Elo on the arena scale where random moves are 0. red from -204 at generation 0 to 1222 at generation 17; black from -155 at generation 0 to 1191 at generation 22. Reference lines mark random moves and minimax searches of depth 1 to 6. -400 -200 0 200 400 600 800 1000 1200 1400 random moves 1-ply search 2-ply search 3-ply search 4-ply search 5-ply search 6-ply search 1k 10k 100k 1M 10M 100M start self-play games (log scale) red generation 0: Elo -204 (95% interval -227 to -182), 0 games red generation 1: Elo 879 (95% interval 855 to 906), 2,000 games red generation 2: Elo 954 (95% interval 931 to 982), 4,000 games red generation 3: Elo 1001 (95% interval 978 to 1028), 14,000 games red generation 4: Elo 959 (95% interval 934 to 986), 16,000 games red generation 5: Elo 1008 (95% interval 984 to 1033), 24,000 games red generation 6: Elo 1049 (95% interval 1025 to 1076), 34,000 games red generation 7: Elo 1085 (95% interval 1062 to 1113), 56,283 games red generation 8: Elo 1067 (95% interval 1044 to 1094), 111,427 games red generation 9: Elo 1078 (95% interval 1055 to 1106), 458,613 games red generation 10: Elo 1127 (95% interval 1104 to 1154), 614,583 games red generation 11: Elo 1132 (95% interval 1107 to 1159), 823,596 games red generation 12: Elo 1156 (95% interval 1131 to 1184), 3,559,501 games red generation 13: Elo 1175 (95% interval 1151 to 1204), 4,326,594 games red generation 14: Elo 1177 (95% interval 1153 to 1205), 5,258,572 games red generation 15: Elo 1182 (95% interval 1157 to 1209), 9,508,572 games red generation 16: Elo 1184 (95% interval 1161 to 1210), 10,758,572 games red generation 17: Elo 1222 (95% interval 1196 to 1249), 15,008,572 games black generation 0: Elo -155 (95% interval -178 to -134), 0 games black generation 1: Elo 800 (95% interval 774 to 829), 2,000 games black generation 2: Elo 921 (95% interval 896 to 948), 4,000 games black generation 3: Elo 963 (95% interval 937 to 990), 8,000 games black generation 4: Elo 967 (95% interval 944 to 995), 14,000 games black generation 5: Elo 1022 (95% interval 999 to 1048), 18,000 games black generation 6: Elo 1023 (95% interval 999 to 1048), 26,000 games black generation 7: Elo 1037 (95% interval 1013 to 1063), 51,051 games black generation 8: Elo 1044 (95% interval 1019 to 1073), 56,283 games black generation 9: Elo 1068 (95% interval 1045 to 1095), 79,192 games black generation 10: Elo 1084 (95% interval 1058 to 1111), 156,784 games black generation 11: Elo 1078 (95% interval 1056 to 1106), 181,496 games black generation 12: Elo 1108 (95% interval 1083 to 1137), 359,338 games black generation 13: Elo 1102 (95% interval 1078 to 1128), 481,543 games black generation 14: Elo 1107 (95% interval 1081 to 1134), 784,378 games black generation 15: Elo 1117 (95% interval 1093 to 1144), 823,596 games black generation 16: Elo 1098 (95% interval 1074 to 1125), 908,013 games black generation 17: Elo 1131 (95% interval 1106 to 1158), 953,413 games black generation 18: Elo 1170 (95% interval 1147 to 1200), 2,656,157 games black generation 19: Elo 1159 (95% interval 1134 to 1186), 8,508,572 games black generation 20: Elo 1167 (95% interval 1141 to 1194), 10,258,572 games black generation 21: Elo 1195 (95% interval 1169 to 1221), 15,008,572 games black generation 22: Elo 1191 (95% interval 1167 to 1219), 19,008,572 games
Each marker is a promoted generation. Circles and the solid line: the red network (96 hidden units). Squares and the dashed line: the black network (64 hidden units). Dotted lines are the fixed opponents. Hover a marker for its interval.

The black network first played roughly even with a 4-ply search at generation 18, after 2,656,157 self-play games and 51 minutes of training. It scored 51.9% (95% interval 47.0% to 56.7%), which is not clearly better than an even score.

Final generation of each network: Elo with its 95% interval, and its score against each search depth (a draw counts as half).
Network Generation Elo 1-ply2-ply3-ply4-ply5-ply6-ply
red (96 hidden units) 17 1,222 (1,196 to 1,249) 100.0%85.4%75.5%57.3%55.1%43.5%
black (64 hidden units) 22 1,191 (1,167 to 1,219) 100.0%84.1%70.9%56.5%51.4%38.5%

Hardware: one desktop computer. The networks are small, so self-play and search ran on its processor, and its graphics card sat mostly idle.

Live in your browser

Watch them, play them, train your own