Chess Assistant 23 & Chess Assistant 22
Chess Assistant 23 combines advanced game database management, analysis powered by the strongest engines, the advanced Tree mode, Opening Encyclopedia and many other features.

Chess Assistant 23 €75.96
Chess Assistant 22 €47.48 » About

About ChessOK

Our business is chess and our goal is to help you enjoy and improve your game. ChessOK is a leading developer of innovative chess software for the PC and the mobile market. We market and sell our products world-wide, both directly and through our resellers. ChessOK traces its roots all the way back to 1988, when the development of Chess Assistant, our chess database powerhouse, was started. Since then we have expanded in all directions. Our software catalog covers the need of every chess player, from the absolute beginner to the strongest grandmasters. We offer software for all aspects of training, studying and improving your chess.

Our Products

Below we present a short summary of our major product categories which highlight our commitment to all aspects of enjoying and improving your game through powerful and innovative software.
  • Rybka & Aquarium. Rybka is by far the strongest chess engine and the computer world chess champion. Our Rybka family of products was developed to allow users to take full advantage of Rybka’s amazing power through effective and innovative analysis methods. Besides Rybka herself (single- and multi-processor versions) we offer our new and modern user interface, Aquarium, which was developed specifically for Rybka. Aquarium is available bundled with Rybka 3 as well as a standalone product at a lower price.
  • Chess Assistant and Databases. This product category comprises Chess Assistant, the chess database powerhouse, and our extensive chess databases. Chess Assistant includes the Rybka chess engine, so we have an overlap with the Rybka family described above. Chess Assistant is also available in various combinations with our database products. All our database products are also compatible with Aquarium. They include a database of 3,5 million games and a correspondence chess database with 370,000 games. For opening studies we offer Chess Opening Encyclopedia and databases with tens of millions of positions analyzed by Rybka and other chess engines. In the endgame department our 12 DVD set of Gold Nalimov Tablebases answer your questions about 3-4-5 and 6 piece endings.
  • Chess Training Programs. We are proud of our training programs which were developed in cooperation with some of our best trainers. They are based on a proven training methodology and have shown themselves to be invaluable tools for improving chess players all over the world. Our products cover the training needs of every chess player from the total beginner to the grandmaster level. Every aspect of the game is covered from the opening to the middlegame and the endgame and from strategy to tactics. And for those who want to learn chess, we teach the rules and show how the pieces move in the award winning Dinosaur Chess.
  • Pocket Software (Handhelds & Cell Phones; Symbian & Java). As handheld devices have become more powerful they have also become more popular for playing and studying chess. ChessOK is already offering a range of products for these platforms. No fewer than 16 different programs are available. Many of them are training programs. Pocket Champion is an example of a chess playing program on the Pocket PC with a range of options. We even offer programs for mobile devices to play on the ChessOK internet server, The Playing Zone.
  • Opening Encyclopedias. In this category we offer a general opening reference along with several products, each focusing on a single opening. These have been prepared by our chess masters, including GM Alexander Kalinin.
  • Game Collections. We have published several annotated game collections of the world champions. Our current catalog includes Alexander Alekhine, Emanuel Lasker, Mikhail Tal, Jose Raul Capablanca, Mikhail Botvinnik and Boris Spassky.
For detailed information about all our software products and demo versions, see Software.

Free Services

ChessOK provides several valuable services for free to chess players.
  • The Playing Zone is an internet chess server run by ChessOK where you can play online absolutely free. Games from the most important chess events are broadcast on the Playing Zone, with live Rybka analysis. A client for the Playing Zone is included with our major products such as Aquarium and Chess Assistant. The client is also available as a free download. Additionally a flash interface is available allowing you to play through your browser.
  • Weekly Games in PGN Format. ChessOK provides free weekly chess databases containing 2000-3000 new games in PGN format. Download and view or analyze in Rybka 3 Aquarium or Chess Assistant 10.
  • Web Broadcasts. Most of our Playing Zone broadcasts are simultaneously broadast on the web allowing you to watch them in your browsers. Games from previous broadcasts can also be replayed or downloaded.
  • Opening Tree. This service provides web acess to the Opening Tree mode from Chess Assistant, based on over 3 million games. See the statistics for each opening positions!
  • Nalimov Tablebases online. This service offers online access to to all 3-4-5-6 pieces Nalimov Tablebases. Here you can receive evaluations and variants for all 3-4-5-6 piece endings with 100% probability.
  • Play Against Rybka! Test your chess skills and challenge one of the strongest chess playing programs in the world without leaving your browser. Three levels of difficulty.
  • Solve Chess Puzzles Online. Do you like chess puzzles? Then check your chess skills by solving our chess tasks! There are 1200 chess puzzles of different level from beginners to intermediate players available.

Contact us

If you have any question or suggestion, don’t hesitate to contact us. Full contact information can be found on the Contact Us page.

Study chess online on Chess King Learn! Time-proven training courses, thousands of examples and exercises.

Start playing right now in your web browser on Chess King Playing Zone! Teams, tournaments, training, analysis and much more!

Download weekly chess database updates (containing 2000+ games) with latest tournaments and games in PGN and Chess Assistant format.

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