Aquarium 2026

Fast, strong, solid!

What's new in ChessOK Aquarium 2026:

• 1-month Chess King LEARN subscription, giving access to 135+ courses available both on the website and in mobile apps! The courses are available in 9 European languages, sorted by category and difficulty level, and include such gems as Chess Tactics for Beginners 2.0, Chess: From Beginner to Club Player, Chess Strategy, Chess Middlegame series, several courses from CT-ART and Chess Tactics in the Opening series and more.
• Updated databases now contain 9.55 million games in total!
• Weekly updates of about 10 000 new games until the end of 2026
• ChessOK Aquarium 2026 auto-installs the strongest chess engine Stockfish 17.1 upon the first launch. Stockfish is leading in most independent computer chess rating lists. No serious chess player can be without Stockfish!

Quick Overview

ChessOK Aquarium 2026 offers advanced analysis functions, game commenting, searching, powerful chess trees, playing, databases and much more.

Interactive Deep Analysis is the the most advanced chess analysis method available today.

Infinite Analysis is more flexible than ever with analysis presets.

Find Blunders and Game Analysis for analyzing whole games.

You also receive 1-month access to all courses at Chess King Learn. The collection includes courses on all topics and for all levels of play. Use your product key as a promo code to activate the subscription.

To activate your Chess King Learn subscription, go to https://learn.chessking.com/learning/purchases/buy, log in or register an account if you don't have one, and use your product key as a promo code.

• ChessOK Aquarium 2026 auto-installs the strongest chess engine Stockfish 17.1, in addition to the good old Rybka 4 that comes with the package. Stockfish is leading in most independent computer chess rating lists. No serious chess player can be without Stockfish!

Play against the computer. Choose from three different strength handicap methods, material handicap or time handicap. You can also just set the ELO level you want to play against!

Publish your games, analyses or even whole chess books! Publish as Aquarium iBook, on the web/blog or in print.

Compatibility with major opening book and database formats.

Databases of about 9.55 million games in total (up to November 11, 2025) that can be updated from www.chessok.com each week with 1500 new games for free.

Language versions: English, German, Spanish, Italian, French and Russian.

System requirements: PC, 256 MB RAM, 4GB of free disk space, Windows Vista/7/8/10/11.