Stefan Pohl Computer Chess

Latest Website-News (2026/03/04): Testrun of Alexandria 9.0 finished: +25 Celo to Alexandria 8.1.12. Alexandria jumped from rank #9 to rank #7.

 

My gift to the community - a much better cutechessGUI. Made by Patrick Leonhardt (PlentyChess), payed for the work by me. Learn more about new cutechess on talkchess and download it right here 

Please mention, this is an early release, bugs are still possible - please report them on talkchess or contact me.

 

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: Reckless 0.9.0

 

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: 2026/03/04: Alexandria 9.0 (+25 Celo to Alexandria 8.1.12)

 

(Ordo-calculation fixed to Stockfish 17.1 = 3854 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

Download all interesting wins (filtered by EAS-Tool) from the full UHO Ratinglist here

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

 

(best Stockfish Celo: Stockfish 260218: 3876 Celo, latest full release (Stockfish 18) has 3873 Celo)

     Program                    Celo    +    - Games    Score   Av.Op. Draws

   1 Stockfish 260218 a512    : 3877    4    4 15000    67.6%   3744   49.0%
   2 Stockfish 18 260131      : 3873    4    4 15000    67.1%   3745   48.9%
   3 Reckless 260108 a512     : 3822    4    4 15000    60.1%   3748   48.7%
   4 Torch 4a a512            : 3815    4    4 15000    59.1%   3748   49.7%
   5 PlentyChess 7.0.37       : 3799    4    4 15000    56.9%   3749   48.7%
   6 Obsidian 250706 a512     : 3783    4    4 15000    54.5%   3750   50.1%
   7 Alexandria 9.0 a512      : 3757    4    4 15000    50.7%   3752   49.4%
   8 Integral 250805 a512     : 3750    4    4 15000    49.7%   3753   50.4%
   9 Berserk 250606 a512      : 3736    4    4 15000    47.6%   3754   50.1%
  10 Viridithas 19.0 a512     : 3722    4    4 15000    45.6%   3755   49.3%
  11 Caissa 1.24 a512         : 3691    4    4 15000    41.1%   3757   50.4%
  12 Clover 9.1 a512          : 3689    4    4 15000    40.8%   3757   50.9%
  13 KomodoDragon 3.3 avx2    : 3687    4    4 15000    40.5%   3757   49.2%
  14 Halogen 16.0 a512        : 3685    4    4 15000    40.2%   3757   49.5%
  15 Tarnished 5.0 a512       : 3680    4    4 15000    39.5%   3757   50.1%
  16 Pawnocchio 1.9 a512      : 3675    4    4 15000    38.9%   3758   50.6%

 

Games        : 120000 (finished)
White Wins   : 59349 (49.5%)
Black Wins   : 1025   (0.9%)
Draws        : 59626 (49.7%)

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 260218 a512    :    3886     11    7500  5375  1932   193  84.5      99
   2 Stockfish 18 260131      :    3873   ----    7500  5271  1985   244  83.5     100
   3 Reckless 260108 a512     :    3725     10    7500  3766  2885   849  69.4     100
   4 Torch 4a a512            :    3711     10    7500  3645  2885   970  67.8     100
   5 PlentyChess 7.0.37       :    3670     10    7500  3205  3052  1243  63.1     100
   6 Obsidian 250706 a512     :    3635     10    7500  2826  3180  1494  58.9     100
   7 Alexandria 9.0 a512      :    3574     10    7500  2192  3305  2003  51.3     100
   8 Integral 250805 a512     :    3560     10    7500  2085  3253  2162  49.5     100
   9 Berserk 250606 a512      :    3526     10    7500  1729  3308  2463  45.1     100
  10 Viridithas 19.0 a512     :    3497     10    7500  1460  3288  2752  41.4     100
  11 Caissa 1.24 a512         :    3427     10    7500   963  2984  3553  32.7      90
  12 KomodoDragon 3.3 avx2    :    3421     10    7500   935  2938  3627  32.1      61
  13 Clover 9.1 a512          :    3420     10    7500   891  3004  3605  31.9      84
  14 Halogen 16.0 a512        :    3416     10    7500   888  2934  3678  31.4     100
  15 Tarnished 5.0 a512       :    3399     10    7500   761  2902  3837  29.5     100
  16 Pawnocchio 1.9 a512      :    3385     10    7500   717  2747  4036  27.9     ---

 

------------------------------------------------------------------- 
--- Number of all Gamepairs          : 60000 
--- Number of drawn Gamepairs overall: 23291 (= 38.82%) 
--- Number of 1:1 drawn Gamepairs    : 11462 (= 19.10%) 
--- Number of 2-draws drawn Gamepairs: 11829 (= 19.71%) 
------------------------------------------------------------------- 

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

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"...