Chess Openings & Repertoire

A chess opening trainer that helps you learn your openings and remember them. Build a repertoire, train it with spaced-repetition reviews, and sharpen it with 80,000+ puzzles taken from real games — with a strong chess engine built in. Whether you open 1.e4, 1.d4 or something less common, there is a line to learn and a puzzle from your opening waiting for you. 📚 YOUR REPERTOIRE, REMEMBERED Add the lines you play as White and Black, learn them move by move, then recall them from memory. Reviews come back just before you would forget, so your lines stay sharp without hours of study. Each move comes with the idea behind it. 📅 A PLAN FOR EVERY DAY Three short steps a day — review your lines, meet a new opening, solve puzzles — in about 10–15 minutes. Keep your streak and level up as you go. ♟️ 80,000+ OPENING PUZZLES Positions from real games and classic opening traps, sorted by opening: Sicilian, Queen's Gambit, Italian Game, French, Caro-Kann, Ruy Lopez, London System, King's Indian, Slav, Nimzo-Indian, English, Scotch, Vienna, King's Gambit and many more. Puzzles adapt to your rating, from beginner to 2200+. 📖 OPENING EXPLORER Browse 12,000+ named openings and variations. See the main replies, how often each move is played, and add any line to your repertoire with one tap. 🔎 SCOUT YOUR OPPONENT Preparing for a tournament game? Import an opponent's games from Lichess or Chess.com, see the openings they play and where they go wrong, and drill a plan against them. 🤖 PLAY THE ENGINE Play Altair, our own neural-network chess engine, on 8 levels from about 800 to 2350 Elo, with or without a clock, plus Chess960. Test your repertoire in a real game, then review it move by move. 🔍 ANALYSIS Analyse any position or game with the built-in engine: best lines, evaluation and the move you should have played. ⚡ PUZZLE SMASH Solve as many puzzles as you can in 3 or 5 minutes, or survive with 3 lives. 💡 HINTS THAT TEACH Stuck? A hint points you in the right direction without giving the move away. 📴 WORKS OFFLINE Puzzles, your repertoire and the engine run on your phone — train on a train, on a plane, anywhere. 🎨 MAKE IT YOURS Board themes, piece sets and app themes, light or dark. 📊 TRACK YOUR PROGRESS Rating, accuracy by opening, solved puzzles and your weakest lines — see what to train next. Available in English and Polish. Free to use with ads; some features have a daily limit. Premium removes the ads and the limits.