Stefan Pohl Computer Chess

Latest Website-News (2026/06/15): Testrun of Raphael 260609 (dev taken from official GitHub) finished: Raphael entered the UHO-Top15 Ratinglist and kicked Clover 9.1 out.

Testrun of Tarnished 6.0 finished: +21 Celo to Tarnished 5.0: Tarnished re-entered the UHO-Top15 Ratinglist and kicked Hobbes 2.1 out.

 

Ceres Binary here, Ceres Installation Guide here, Ceres Nets here

 

Dont forget to take a look at my EAS-Ratinglist (The world's first engine-ratinglist not measuring strength of engines, but engines's style of play). 

 

Next testrun: Stockfish 260614

 

Stay tuned.

UHO-Top15 Engines Ratinglist (+ regular testing of Stockfish Dev-versions)

 

 

Playing conditions:

 

The 15 strongest engines and the latest StockfishDev version are playing 1000 games vs. each opponent: 15000 games per engine are played. A RoundRobin Tournament with 120000 games overall !

 

Hardware: AMD Ryzen 9 7945HX 16-core (32 threads) notebook with 64GB RAM (since 2024/10/08), 2 identical machines. Windows 11 64bit

Speed: (singlethread, TurboBoost-mode switched off, chess starting position) Stockfish 17: 600 kn/s (when 26 games are running simultaneously)

Hash: 512MB per engine

GUI: Cutechess-cli (GUI ends game, when a 5-piece endgame is on the board, all other games are played until mate or draw by chess-rules (3fold, 50-moves, stalemate))

Tablebases: None for engines, 5 Syzygy for cutechess-cli

Openings: My UHO_2022_6mvs_+120_+129 openings are used (first 500 lines) (UHO 2022 openings are part of my Anti Draw Openings download-package). 

Ponder, Large Memory Pages & learning: Off

Thinking time: 3min+1sec per game/engine. One testrun (15000 games) takes around 80-85 hours (=3.5 days)

The version-numbers of the Stockfish engines are the date of the latest patch, which was included in the Stockfish sourcecode, not the release-date of the engine-file, written backwards (year,month,day))(example: 200807 = August, 7, 2020). The used SF compile is the AVX512-compile, which is the fastest on my AMD Ryzen CPU. SF binaries are taken from https://github.com/official-stockfish/Stockfish/releases (except the official SF-release versions, which are taken form the official Stockfish website).

Read the explanation, why I chose my testing-conditions, like I did here

 

Latest update: 2026/06/15: Raphael 260609 (new engine) and Tarnished 6.0 (+21 Celo to Tarnished 5.0)

 

(Ordo-calculation fixed to Stockfish 18 = 3873 Celo. Mention, there are no human or "realistic" Elo numbers in enginechess, since the engines reached superhuman strength, so I decided to use "Celo" (=Computer Elo) instead)

 

See the tournament cross-table as a picture (done by Fritz20 GUI) here

See the individual statistics of engine-results here

See the Engines Aggressiveness Score Ratinglist here

See the Gamepair-statistics of the UHO-Top15 Ratinglist here

See the full UHO Ratinglist (with EAS-Ratinglist): here

Download the current gamebase, the full-list gamebase and the archive here

See the old SPCC-Ratinglist (full list) and EAS-List from 2020 until 2023/08/28: here

 

(best Stockfish Celo: Stockfish 260606: 3889 Celo, latest full release (Stockfish 18) has 3873 Celo)

     Program                     Celo    +    - Games    Score   Av.Op. Draws

   1 Stockfish 260606          : 3888    4    4 15000    67.9%   3754   48.8%
   2 Stockfish 18 260131       : 3873    4    4 15000    65.9%   3755   48.9%
   3 Reckless 260502 a512      : 3839    4    4 15000    61.2%   3758   48.6%
   4 Torch 4d a512             : 3824    4    4 15000    59.0%   3759   49.8%
   5 PlentyChess 7.0.37        : 3797    4    4 15000    55.2%   3760   48.5%
   6 Obsidian 250706 a512      : 3779    4    4 15000    52.4%   3762   49.3%
   7 Alexandria 9.0 a512       : 3752    4    4 15000    48.5%   3763   48.7%
   8 Pawnocchio 260527 a512    : 3749    4    4 15000    48.1%   3764   49.4%
   9 Integral 250805 a512      : 3748    4    4 15000    47.9%   3764   50.3%
  10 Berserk 14.0 a512         : 3733    4    4 15000    45.8%   3765   49.3%
  11 Viridithas 19.0 a512      : 3717    4    4 15000    43.4%   3766   49.2%
  12 Raphael 260609 a512       : 3710    4    4 15000    42.3%   3766   49.1%
  13 Halogen 16.5 a512         : 3701    4    4 15000    41.1%   3767   48.7%
  14 Tarnished 6.0 a512        : 3698    4    4 15000    40.6%   3767   49.5%
  15 Caissa 1.25 a512          : 3698    4    4 15000    40.6%   3767   49.3%
  16 Quanticade 260519 a512    : 3695    4    4 15000    40.2%   3767   48.1%

 

Games        : 120000 (finished)
White Wins   : 60160 (50.1%)
Black Wins   : 928    (0.8%)
Draws        : 58912 (49.1%)

Below the UHO-Top15 Ratinglist, recalculated with Gamepairs (using my Gamepair Rescoring Tool V1.5), Ordo-calculation fixed to Stockfish 17.1 = 3854 Celo, realizing Vondele's (Stockfish Maintainer) idea: "Thinking uniquely in game pairs makes sense with the biased openings used these days. While pentanomial makes  sense it is a bit complicated so we could simplify and score game pairs only (not games) as W-L-D (a traditional score of 2-0, or 1.5-0.5 is just a W)."

Mention, the errorbar here is +/-5.5 Celo (=11 overall Error), compared to +/-4 Celo in the classical ratinglist above (=1.375 wider errorbar here). But the result-gaps are (at least) 2x up to 2.5x bigger (in average), calculating with gamepairs. So, the statistical reliability of the results is much better in the Gamepair-ratinglist, compared to the classical ratinglist...

CFS means Chance For Superiority in percent, calculated by ORDO.

See the head-to-head gamepair-statistics of the UHO-Top15 Ratinglist here

   # PLAYER                    :    Celo  Error   Pairs     W     D     L   (%)  CFS(%)
   1 Stockfish 260606          :    3920     11    7500  5412  1926   162  85.0     100
   2 Stockfish 18 260131       :    3873   ----    7500  4989  2199   312  81.2     100
   3 Reckless 260502 a512      :    3777     10    7500  3981  2803   716  71.8     100
   4 Torch 4d a512             :    3740     10    7500  3544  3062   894  67.7     100
   5 PlentyChess 7.0.37        :    3674     10    7500  2834  3291  1375  59.7     100
   6 Obsidian 250706 a512      :    3635     10    7500  2439  3342  1719  54.8     100
   7 Alexandria 9.0 a512       :    3575     10    7500  1801  3439  2260  46.9      93
   8 Pawnocchio 260527 a512    :    3569     10    7500  1796  3327  2377  46.1      64
   9 Integral 250805 a512      :    3568     10    7500  1762  3365  2373  45.9     100
  10 Berserk 14.0 a512         :    3534     10    7500  1433  3361  2706  41.5     100
  11 Viridithas 19.0 a512      :    3500     10    7500  1150  3266  3084  37.1     100
  12 Raphael 260609 a512       :    3479     10    7500  1020  3143  3337  34.6     100
  13 Halogen 16.5 a512         :    3468     10    7500   912  3155  3433  33.2     100
  14 Tarnished 6.0 a512        :    3457     10    7500   871  3033  3596  31.8      61
  15 Caissa 1.25 a512          :    3456     10    7500   843  3067  3590  31.7      92
  16 Quanticade 260519 a512    :    3450     10    7500   810  3027  3663  31.0     ---

 

------------------------------------------------------------------- 
--- Number of all Gamepairs          : 60000 
--- Number of drawn Gamepairs overall: 24403 (= 40.67%) 
--- Number of 1:1 drawn Gamepairs    : 12425 (= 20.71%) 
--- Number of 2-draws drawn Gamepairs: 11978 (= 19.96%) 
------------------------------------------------------------------- 

Aborted testruns, because the tested engine was too weak to enter the UHO-Top15 Ratinglist:

Icarus 1.1, Raphael 4.0, Heimdall 1.4.1, Renegade 1.2.0, Igel 3.6.0, Minic 3.41, Booot 7.3, Black Marlin 9.0, Equisetum 1.0, Clarity 8

Below you find a diagram of the progress of Stockfish in my tests since February 2026. 

And below that diagram, the older diagrams.

 

You can save the diagrams on your PC with mouseclick (right button) and then choose "save image"...