A free chess site built on Blizzard. Play people online with ratings, take on ten Blizzard bots from beginner to full strength, review every game with the engine, solve puzzles and join hourly arenas. No ads, nothing to pay.

Blizzard has no board of its own. It runs inside a chess program, just like Stockfish: the program shows the board, and Blizzard finds the moves.

Connect it

1. Unzip the archive

   Into any folder, for example Documents\Chess. There is no need to double-click blizzard.exe: that only opens a console window where the engine waits for commands.

2. Add it to your chess program

3. Adjust if you like

   Skill Level

   Strength from 1 (beginner) to 10 (full).

   Hash

   Memory for the search, in MB. 32–256 is plenty.

   MultiPV

   How many best lines to show while analysing.

   OwnBook

   Play the opening from its grandmaster book.

Each version plays a match against the previous one before it comes out. Open a version to see what changed.

Against Stockfish 2800

The same opponent for every version: score after a series of games, 0.2 s per move, book openings played with both colors.

This is not a FIDE or CCRL rating. A lightweight Stockfish at limited strength usually plays below its nominal rating, so these numbers are most useful for comparing Blizzard versions with each other: they are measured under the same conditions.