Leela Chess Zero

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Leela Chess Zero
Original author(s)Gian-Carlo Pascutto, Gary Linscott
Developer(s)Gary Linscott, Alexander Lyashuk, others
Initial release9 January 2018; 10 months ago (2018-01-09)
Stable release
v0.19.0 / 19 November 2018; 19 days ago (2018-11-19)
Repository Edit this at Wikidata
TypeChess engine

Leela Chess Zero is a free and open-source chess engine and distributed computing project. Development has been spearheaded by programmer Gary Linscott, who is also a developer for the Stockfish chess engine. Leela Chess Zero was adapted from the Leela Zero Go engine,[1] which in turn was based on Google's AlphaGo Zero project,[2] also to verify the methods in the AlphaZero paper as applied to the game of chess.

Like Leela Zero and AlphaGo Zero, Leela Chess Zero only knows the basic rules and nothing more.[1] Leela Chess Zero is trained by a distributed computing network coordinated at the Leela Chess Zero website. As of August 2018, it had trained itself by playing over 23 million games of chess against itself.[1]


The Leela Chess Zero project was first announced on TalkChess.com on January 9, 2018.[1][3] Within the first few months of training, Leela Chess Zero had already reached the Grandmaster level, surpassing the strength of early releases of Rybka, Stockfish, and Komodo, despite evaluating orders of magnitude fewer positions while using MCTS search.

Competition results[edit]

In April 2018, Leela Chess Zero became the first neural network engine to enter the Top Chess Engine Championship (TCEC), during season 12 in the lowest division, 4.[4] Leela did not perform well: in 28 games, it won one, drew two, and lost the remainder; its sole victory came from a position in which its opponent, Scorpio 2.82, crashed.[5] However, it improved quickly. In July 2018, Leela placed seventh out of eight competitors at the 2018 World Computer Chess Championship,[6] and in the next TCEC season, it won division 4 with a record of 14 wins, 12 draws, and 2 losses.[7] After being promoted to division 3, Leela tied for 2nd place with Arasan, but did not advance. (In the event of ties, direct encounters between the tied engines decide promotion.) Its record in division 3 was 7 wins, 18 draws, and 3 losses.[7]

In September 2018, Leela participated in the 2018 Chess.com Computer Chess Championship (CCCC).[8] In round 1, it placed fifth out of 24 entrants. The top eight engines advanced to round 2, where Leela placed fourth.[9][10] Leela then won the 30 game match against Komodo to secure 3rd place in the tournament.[11][12]

Concurrently, Leela participated in the TCEC cup, a new event in which engines from different TCEC divisions can play matches against one another. Leela defeated higher-division engines Laser, Ethereal and Fire before finally being eliminated by Stockfish in the semi-finals.[13]

In October and November 2018, Leela participated in the Chess.com Computer Chess Championship Blitz Battle.[14] Leela finished third behind Stockfish and Komodo.[15]

In December 2018, Leela participated in season 14 of the Top Chess Engine Championship. Leela finished first in division 3 with 18 wins, 9 draws, and 1 loss.[16] Leela then advanced to division 2, which is ongoing.

Notable games[edit]

See also[edit]


  1. ^ a b c d Silver, Albert (26 April 2018). "Leela Chess Zero: AlphaZero for the PC". Chess News. Retrieved 11 June 2018.
  2. ^ "leela-zero". GitHub. Retrieved 27 April 2018.
  3. ^ "Announcing lczero". TalkChess.com. Retrieved 11 June 2018.
  4. ^ "Breaking: Leela Chess Zero enters TCEC Season 12". Chessdom. 18 April 2018.
  5. ^ See the season 12 archives at http://tcec.chessdom.com/archive.php
  6. ^ "World Computer Chess Championship 2018". ICGA. Retrieved 19 July 2018.
  7. ^ a b See the season 13 archives at http://tcec.chessdom.com/archive.php
  8. ^ "Chess.com Computer Chess Championship".
  9. ^ "CCCC stage 2 ended. Leela 4th with a good performance! Stockfish undefeated!". LCZero Blog. 26 September 2018. Retrieved 26 September 2018.
  10. ^ Cilento, Pete (26 September 2018). "Stockfish, Houdini Battle For Computer Chess Championship; Komodo vs Lc0 For 3rd". Chess.com. Retrieved 9 October 2018.
  11. ^ "Leela wins the match series against Komodo and wins a Pawn odds game against Stockfish!". LCZero Blog. 3 October 2018. Retrieved 9 October 2018.
  12. ^ Cilento, Pete (4 October 2018). "Stockfish Wins Computer Chess Championship Rapid; Lc0 Finishes 3rd". Chess.com. Retrieved 9 October 2018.
  13. ^ See the TCEC Cup 1 archives at http://tcec.chessdom.com/archive.php
  14. ^ Cilento, Pete (11 October 2018). "Computer Chess Championship Returns For Blitz Battle". Chess.com. Retrieved 22 November 2018.
  15. ^ Cilento, Pete (19 November 2018). "Stockfish Wins Computer Chess Championship Blitz". Chess.com. Retrieved 22 November 2018.
  16. ^ See the season 14 archives at http://tcec.chessdom.com/archive.php

External links[edit]