Best Free Chess Engines of 2019

A listing of the strongest computer chess engines publicly available in 2019. Includes only those mainly run on cpus and not on gpus. Main development projects only not including hybrids or forks. Estimated Elo rating of the chess programs are enclosed in parenthesis.

Top Chess Engines


1. Stockfish 10 64-bit 4CPU (3463)
2. Komodo 13.0.2 64-bit 4CPU (3401)
3. Houdini 6 64-bit 4CPU (3398)
4. Ethereal 11.53 64-bit 4CPU (3330)
5. Fire 7.1  64-bit 4CPU (3321)
6. Xiphos 0.5 64-bit 4CPU (3316)
7. Komodo 12.3 MCTS 64-bit 4CPU (3294)
8. Laser 1.7 64-bit 4CPU (3282) 
9. Deep Shredder 13 64-bit 4CPU (3282)
10. Fizbo 2 64-bit 4CPU (3276)
11. Andscacs 0.95 64-bit 4CPU (3267)
12. Booot 6.3.1 64-bit 4CPU (3263)
13. RofChade 2.1 64-bit 4CPU (3250)
14. Schooner 2.1 64-bit 4CPU (3213)
15. Defenchess 2.2 64-bit (3210)

Top Free Chess Engines


1. Stockfish 10 64-bit 4CPU (3463)
2. Komodo 10 64-bit 4CPU (3347)
3. Ethereal 11.53 64-bit 4CPU (3330)
4. Fire 7.1 64-bit 4CPU (3321)
5. Xiphos 0.5 64-bit 4CPU (3316)
6. Laser 1.7 64-bit 4CPU (3282)
7. Fizbo 2 64-bit 4CPU (3276)
8. Andscacs 0.95 64-bit 4CPU (3267)
9. Booot 6.3.1 64-bit 4CPU (3263)
10. RofChade 2.1 64-bit 4CPU (3250)
11. Schooner 2.1 64-bit 4CPU (3213)
12. Defenchess 2.2 64-bit (3210)
13. Arasan 21.3 64-bit 4CPU (3195)
14. Houdini 1.5a 64-bit 4CPU (3186)
15. Gull 3 64-bit 4CPU (3181)

Per performance determined by the CCRL

Some known variants of the above chess programs have not been included and earlier versions and even some later versions have been excluded if they had poorer performance ratings.

Free Openings Book for Chess Engines

Free opening books for computer chess or chess GUIs in Chessbase .ctg Arena .abk or more general .bin format are available at the following locations:

1337chess

Hosts opening books developed by Michael Wagner. The free one offered is dated but might provide a glimpse into what some of the stronger opening books might look like.

Arena

A list of opening books submitted by users of the Arena chess program.

HIARCS

Provides opening books used by the HIARCS chess engine.

SedatChess

Sedat Canbaz maintains his Perfect series of opening books at this site.

Terminator

Opening books in Terminator series developed by Sunil Nair.


According to Vladimir of Chess2U's tests the best chess openings books for chess engines are

1. Doom 4a
2. Blue 4
3. The Book of Faca GL
4. Doom D3
5. Terminator  Return of Game of Throne  

Some on the complete list, however, are private and in limited circulation or commercial openings books.

Best Free Chess Downloads - Free Chess Database Software

Chessbase Light 2009

A stripped down version of Chessbase 10 with certain features disabled or removed. It is an update to the earlier Chessbase Light 2007 and much older Chessbase Light. Being based on what is arguably the leading commercial product, it has many excellent features and one of the smoothest and most attractive graphical user interfaces to tempt users to purchase the full flagship Chessbase program.

But there are significant limitations. Creation of new databases is disabled meaning only existing databases can be opened and even then they cannot be edited. Also many features are only easily applied to the first 32000 games of a database making working with larger databases clumsy or impractical. Internet chess is available only via the Playchess server. Finally there is no support for UCI chess engines which restricts the user to Chessbase associated chess engines.

Previously available on the Chessbase website but it has since been removed. You might find it somewhere on the internet with a little searching. 

Arena

A chess GUI with the running of computer chess engine tournaments in mind. UCI support allows the use of a wide selection of chess engines. It can be used as an interface to the Free Internet Chess Server and Internet Chess Club although there are better interfaces for those internet chess servers. It's reported that Arena can be a bit buggy at times.

SCID vs. PC

This is a fork that is being updated pretty frequently based on the Shane's Chess Information Database (SCID) project . The visual presentation and user interface improvements have greatly increased the appeal of its fast if somewhat wonky database capabilities and ability to work with UCI chess engines and various chess servers.

Fritz 5.32

Old but good. Somewhat clunky interface for a commercial program but its unrestricted ability to manipulate both PGN and Chessbase files make it a standout among free programs that can work with chess databases. It can also run engine matches but was mainly designed to play games against. Cannot support UCI or newer engines though and may have some compatibility issues with newer computers. Internet play is not supported either.