Fat Fritz 2

This is Fat Fritz 2, a UCI chess engine forked from Stockfish code from January 2021, with a custom neural network made by Albert Silver for the company ChessBase, now available for free under the GNU GPL 3. Binaries are provided courtesy of Darius at chessengeria.eu. You can find the original downloads of the source code and original ChessBase 64-bit Windows binaries at foss.chessbase.com, but ChessBase did not provide binaries for other platforms besides 64-bit Windows.

Thankfully, Darius at chessengeria.eu has compiled the Fat Fritz 2 code for various other platforms: Linux on ARM32 or ARM64, Linux on Intel x86-64, macOS on Apple Silicon, macOS on Intel x86-64, Windows on Intel x86-32, and Windows on Intel x86-64. If you appreciate Darius's work compiling these builds, please check out his blog on chess engines. Also please support the official release of Stockfish and consider supporting Stockfish thru Fishtest, using some of your computer's processing ability to help improve the official Stockfish releases (which are stronger than Fat Fritz 2).

If what you want is the strongest chess engine of all, I suggest installing the latest Stockfish development build, not Fat Fritz 2. These binaries are mostly just for people curious about Fat Fritz 2 who want to experiment with this controversial chess engine, for example if you do chess engine tournaments between different chess engines you would find these useful.

If you want to know which of the binaries for your platform to use, you should use the fastest one that runs properly on your computer; you do this by running the program on a command line and typing in the "bench" command to get a benchmark of how many positions per second it can do (higher is better). Then to exit the program, you type in the "quit" command. Those commands work with all standard UCI chess engines. Typically this chess engine is used with a chess GUI that can run UCI chess engines. For a list of chess GUIs that can run UCI chess engines, see the Chess Programming Wiki page about UCI section on GUIs.