TOP 20:
# PLAYER : RATING ERROR POINTS PLAYED (%) 1 Stockfish 18-dev 12-11-2025 : 3878 12 1684.5 2708 62.2% 2 Stockfish 17.1 : 3866 11 7501.0 11610 64.6% 3 PlentyChess 7.0 : 3845 12 1901.5 3540 53.7% 4 Obsidian 16.14 : 3840 13 1473.0 2660 55.4% 5 Reckless 0.8 : 3839 12 1727.5 3420 50.5% 6 Alexandria 8.1.0 : 3814 12 1300.0 2660 48.9% 7 Clover 9.1 : 3801 12 1137.0 2280 49.9% 8 Lc0 0.31.2 BT3-7464000 1650m : 3798 25 172.5 360 47.9% 9 Berserk 13 : 3789 10 6484.0 12648 51.3% 10 Caissa 1.23 : 3787 15 721.0 1520 47.4% 11 Viridithas 18.0.0 : 3786 16 748.0 1520 49.2% 12 Integral 7.0 : 3785 13 1829.5 3800 48.1% 13 Horsie 1.1 : 3775 13 998.0 2280 43.8% 14 Stormphrax 7.0 : 3766 15 665.0 1520 43.8% 15 Halogen 15 : 3749 16 621.0 1520 40.9% 16 RubiChess 20240817 : 3742 13 1145.0 2660 43.0% 17 Titan 1.1 : 3734 13 1201.5 2660 45.2% 18 KomodoDragon 1.0 : 3699 13 978.0 2660 36.8% 19 Seer 2.8.0 : 3695 13 1010.5 2660 38.0% 20 Koivisto 9.0 : 3688 12 1742.0 3540 49.2%
Updates:
Added Stockfish 18-dev 12-11-2025 (with new TI net), Stormphrax 7.0, Halogen 15. Tested again Stockfish 14 and 14.1.
Click here for the complete rating list:
The rating list – updated as of 23/11/2025 – is calculated with Ordo and was obtained under the following assumptions.
- The Elo rating of Rebel 6 UCI (1994) is fixed at 2450 points, which serves as an “anchor” for all others. This score is the average value of the results obtained by the original version of the engine in various matches against human GMs in the early 90s, derived from various official or unofficial sources (Talkchess.com, Rebel13.nl, computerchessuk.com, various forums…).
- Several electronic chessboards have been added whose strength in terms of Elo obtained through matches with humans is fairly well known. In this way, the rating list should provide engine scores that are more easily comparable with human ones. The electronic chessboards were emulated with CB-Emu, and made to play against several UCI and Winboard engines of similar strength.
- The time per game was set to 40/120′ repeated, reparameterized to the processing speed of a Pentium 90. The execution speed of the latter was emulated, and through various benchmarks done in the past on real P90 machines, I tried to obtain a value as close as possible to reality. Consequently, on modern PCs the actual time per game was 40/125” or 40/130” (seconds) depending on the PC used for the test, comparable to other blitz tests found on the net. For some engines, such as Chess Titans, it was not possible to define a game time; for this reason, I have indicated the characteristics of the CPU on which it was tested.
- The opening suite consists of 190 different positions, repeated for each engine (each engine played the same opening both as white and black). For older engines, not equipped with a UCI or XBoard interface (such as the 1988 version of BattleChess), I manually reproduced the various moves suggested by the programs. Also for these engines, as for all the others, the playing time was reparameterized to the performance of a Pentium 90. For this reason, the games of these engines are few compared to the total, and based on random selections of the 190 openings. The opening suite can be downloaded here.
- All the chess engines used are freely available on the net, with the exception of commercial programs that I purchased years ago, and are limited to using only one CPU core.
- In the “Top 10”, I have not included past versions of Stockfish, nor engines derived from it (such as Shashchess). In the complete rating list, I have also included past versions of Stockfish for comparison.
- The main goal of this rating list, made for my exclusive enjoyment, was both to determine the playing level of modern engines compared to past ones, but also to evaluate the actual playing strength of many programs that I loved in my youth (the aforementioned Battlechess, for example).