# Swedish Chess Computer Association

The Swedish Chess Computer Association (Swedish: Svenska schackdatorföreningen, SSDF) is an organization that tests computer chess software by playing chess programs against one another and producing a rating list. On September 26, 2008, the list was released with Deep Rybka 3 leading with an estimated Elo rating of 3238. Rybka's listing in June 2006 was the first time a program on the list has passed the 2900 mark. In the year 2000 the ratings of the chess engines in the SSDF rating pool were calibrated with games played against humans.
The SSDF list is one of the only statistically significant measures of chess engine strength, especially compared to tournaments, because it incorporates the results of thousands of games played on standard hardware at tournament time controls. The list reports not only absolute rating, but also error bars, winning percentages, and recorded moves of played games.
The SSDF's current testing platform includes an AMD Ryzen 7 1800X 8-Core 3.6 GHz with 16 GB of RAM-memory and a 64-bit operating system. On this platform they have chosen to add the 6 piece Syzygy endgame database, installed on SSD, for the programs that are able to use it. From 1984 to 2020, the SSDF top program increased by 1942 points, an average of 54 points per year.

## Rating list year-end leaders

Rating list year-end leaders :
| Year | Program | Hardware | Rating |
| 1984 | Novag Super Constellation | 6502 4 MHz | 1631 |
| 1985 | Mephisto Amsterdam | 68000 12 MHz | 1827 |
| 1986 | Mephisto Amsterdam | 68000 12 MHz | 1827 |
| 1987 | Mephisto Dallas | 68020 14 MHz | 1923 |
| 1988 | Mephisto MM 4 Turbo Kit | 6502 16 MHz | 1993 |
| 1989 | Mephisto Portorose | 68020 12 MHz | 2027 |
| 1990 | Mephisto Portorose | 68030 36 MHz | 2138 |
| 1991 | Mephisto Vancouver | 68030 36 MHz | 2127 |
| 1992 | Chess Machine Schröder 3.0 | ARM2 30 MHz | 2174 |
| 1993 | Mephisto Genius 2.0 | 486/50-66 MHz | 2235 |
| 1995 | MChess Pro 5.0 | Pentium 90 MHz | 2306 |
| 1996 | Rebel 8.0 | Pentium 90 MHz | 2337 |
| 1997 | HIARCS 6.0 | 49MB P200 MMX | 2418 |
| 1998 | Fritz 5.0 PB29% | 67MB P200 MMX | 2460 |
| 1999 | Chess Tiger 12.0 DOS | 128MB K6-2 450 MHz | 2594 |
| 2000 | Fritz 6.0 | 128MB K6-2 450 MHz | 2607 |
| 2001 | Chess Tiger 14.0 CB | 256MB Athlon 1200 | 2709 |
| 2002 | Deep Fritz 7.0 | 256MB Athlon 1200 MHz | 2759 |
| 2003 | Shredder 7.04 UCI | 256MB Athlon 1200 MHz | 2791 |
| 2004 | Shredder 8.0 CB | 256MB Athlon 1200 MHz | 2800 |
| 2005 | Shredder 9.0 UCI | 256MB Athlon 1200 MHz | 2808 |
| 2006 | Rybka 1.2 | 256MB Athlon 1200 MHz | 2902 |
| 2007 | Rybka 2.3.1 Arena | 256MB Athlon 1200 MHz | 2935 |
| 2008 | Deep Rybka 3 | 2GB Q6600 2.4 GHz | 3238 |
| 2009 | Deep Rybka 3 | 2GB Q6600 2.4 GHz | 3232 |
| 2010 | Deep Rybka 3 | 2GB Q6600 2.4 GHz | 3227 |
| 2011 | Deep Rybka 4 | 2GB Q6600 2.4 GHz | 3216 |
| 2012 | Deep Rybka 4 x64 | 2GB Q6600 2.4 GHz | 3221 |
| 2013 | Komodo 5.1 MP x64 | 2GB Q6600 2.4 GHz | 3241 |
| 2014 | Komodo 7.0 MP x64 | 2GB Q6600 2.4 GHz | 3295 |
| 2015 | Stockfish 6 MP x64 | 2GB Q6600 2.4 GHz | 3334 |
| 2016 | Komodo 9.1 MP x64 | 2GB Q6600 2.4 GHz | 3366 |
| 2017 | Komodo 11.01 MP x64 | 16GB 1800X 3.6 GHz | 3406 |
| 2018 | Stockfish 9 MP x64 | 16GB 1800X 3.6 GHz | 3502 |
| 2019 | Stockfish 10 MP x64 | 16GB 1800X 3.6 GHz | 3529 |
| 2020 | Stockfish 12 NNUE MP x64 | 16GB 1800X 3.6 GHz | 3573 |