Your blunders are your best teacher.

Yes, and it stays free. The review of your latest game costs nothing and needs no account. A free account adds a drill rotation for your blunders (10 slots), Coach Bjorn 5 a day, 1 set for the Woodpecker method and 2 of 18 theme packs. Premium, at $5.99 a month, is for players who want every blunder drilled and Bjorn on every move.

Type your Chess.com or Lichess username and KingChess reviews your latest game. Stockfish scores every move, the tactics are marked on the board, and Coach Bjorn explains the moments that decided the game. You also see what players at your rating actually play in the same positions. The first half of the game is open to anyone. A free account opens the rest.

Not to start. The review of your latest game works with a username alone. An account is free. It is what lets KingChess keep your games, build drills from your blunders and track them over time, and it links your Chess.com or Lichess account so new games come in as you play.

A game review tells you what went wrong in one game. KingChess is built for what comes after. It reads across your games, finds the mistake you keep making, names the pattern, and drills it from your own positions until it stops showing up. The review is the door. The training behind it is the product.

Every move is scored by Stockfish, the same open-source engine every major chess site uses, running on our servers so your phone does not do the work. What players at your rating actually play comes from a separate model trained on human games at each rating level, so "what a 1400 does here" is measured, not guessed. Coach Bjorn's explanations are checked against the board before he says them.

Chess.com and Lichess. Linked accounts: 1 per platform on the free plan, 3 per platform on Premium, so a main account and an alt both count toward your patterns. Game reviews and drills come from those games. Woodpecker sets can also be built from pasted positions or an uploaded PGN or PDF.

No. Your games on both sites are public, and KingChess reads them by username through each site's public API. Nothing is written to your accounts and there is nothing to authorize. Linking an account only tells KingChess which username is yours.

Every puzzle is a position from your own games, at the move where you went wrong. After solving one you rate it Again, Hard, Good or Easy, and it comes back on a schedule. Good brings it back in 15 minutes, then an hour, then longer each time you get it right. Miss it and you see it again right away. Chess pattern recognition rewards tight intervals, so the gaps are shorter than in most flashcard apps.

The polar bear who does the talking. He explains moves in plain words, and everything he says is checked against the board first, so he never hands you a bare engine line. On the free plan he explains 5 a day. On Premium, 100 a day.

Yes. Every position comes from your own games, so the difficulty is your level by definition. A 1200 drills the mistakes a 1200 makes. A 2000 drills the mistakes a 2000 makes. Most players here are rated under 2000.

Reach and depth. Free reads your last 10 games; Premium reads your last 300, then every new game. Every blunder enters your drills with no slot cap, and Coach Bjorn speaks on every move, up to 100 a day. Premium also opens the Career Report across your whole history, all 18 theme packs and every Woodpecker set. $5.99 a month or $35.99 a year.

Stripe processes every payment. KingChess never sees or stores your card. Cancel anytime from your account settings; access runs to the end of the period you paid for.

Yes. KingChess is a website, so it runs in your phone's browser with nothing to install. The review board, the drills and Coach Bjorn all fit a phone screen.