Explore chess with Chess Blunders
User-Friendly. Open Source. Totaly Free.
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World's Biggest Chess Database
1,743,871 Problems
We collected more than 6 million games from professional tournaments. Our hardware working day and night for last 2 years to analyze them. Our algorithms already choosed 1.7 million of educational posititions for you to solve. You are just few clicks away from infinite chess experience.
Unique Content
Never Seen Before
The problems were generated using newly developed algorithms, ensuring you haven't seen them before. The lack of human intervention allowed us to collect a large number of surprising and awesome positions.
Open and Free
The Freedom to Explore
This project will always remain free and open, because this is what we believe in. All source code is available on Bitbucket and you can use it any way you want. We provide an API to access our database for both research and fun, but we also provide the raw data we used for this service.
Like. Discuss. Share
Our service promotes interactions between users. You can comment on positions you like, store favorites, and share your progress with the community.
Powered by Stockfish
Strongest Open Source Engine
Using modern technology we explore the thought process and failures made by great players. We use the best available technologies, therefore we choose the strongest open source chess engine as a judge.
Mobile client
Play everywhere
Using our official mobile client you can play and improve your skills everywhere and everytime.
It Is Not Our Business
We put a lot of effort to keep your privacy at hight level. We don't save your password, we don't require your mail and we don't share your personal data with anybody. We also don't send you any proposals or ads.
19+ Third-Party Tools
Technology is the key to making great software. This project written with fun and learning for you to learn and have fun. We use Python, Flask, Redis, uWSGI, MongoDB, Pymongo, Chardet, Pychess, Stockfish, Bcrypt, PostgreSQL, Psycopg2, Highlight.js, jQPlot, jQuery, Notify.js, Chess.js, Chessboard.js, js-url, simplePagination, Font Awesome and more. Mobile client written using Ionic framework, ChessboardJS, LokiJS, nvd3 and more.
Who are these people?
We are more interested in feedback than fame or copyright, so we'll just give you the e-mail to contact us: