Welcome to the CCRL (Computer Chess Rating Lists) website.

CCRL was formed in 2006 with the founding members being Graham Banks, Ray Banks, Sarah Bird, Kirill Kryukov and Charles Smith. Other testers have since been invited to join. Currently active testers are Graham Banks, Charles Smith, Ray Banks (FRC only), Sergio Martinez and Gabor Szots.

Basically we are a group of computer chess enthusiasts who enjoy engine v engine testing. We thought that our hobby would be more meaningful if we combined our results by being part of a group. Although we have a constitution plus set guidelines on testing conditions, testers have freedom of choice as to what they wish to test and how. For example, some use a systematic process, whereas others prefer to run tournaments.

The latest CCRL Rating Lists and Statistics are available for viewing from the following links:

Please note that the three lists are updated separately to each other.

The links to the various rating lists can be found just beneath the default Best Versions list. For example there is a 32-bit Single CPU list.

Our 40 moves in 40 minutes repeating and 40 moves in 4 minutes repeating are both adjusted to the AMD64 X2 4600+ (2.4GHz). On more modern Intel hardware, this would be about 40 moves in 15 minutes repeating and 40 moves in 1.5 minutes repeating. We test using generic books with a limit of 12 moves depth rather than using the engines' own books, plus we test using ponder off.

Be aware that in the early stages of testing, an engine's rating can often fluctuate a lot. It is strongly advised to look at the many other rating lists available in order to get a more accurate overall picture of an engine's rating relative to others.

The LOS (likelihood of superiority) stats to the right hand side of each rating list tell you the likelihood in percentage terms of each engine being superior to the engine directly below them. All games are available for download by engine, by month or by ECO code. ELO ratings are now saved in all game databases for those engines that have 200 games or more. Clicking on an engine name will give details as to opponents played plus homepage links where applicable. Custom lists of engines can be selected for comparison. An openings report page lists the number of games played by ECO codes with draw percentage and White win percentage. Clicking on a column heading will sort the list by that column.

If you are interested in joining the CCRL testing group, please sign up to our forum and contact one of us. Please be aware that for our own protection, we will only consider accepting testers who are either well known to the computer chess community or can have somebody well known vouch for their authenticity.