How to read a chess game review

To read a chess game review, start with each side's accuracy and the evaluation graph, go straight to the blunders and mistakes, and leave the rest for later. Every move gets a label from how much win chance it gave away compared with the best move, and the reasons that repeat in your errors tell you what to practise.

What do the move labels in a game review mean?

The label comes from the loss, the win chance a move gives away compared with the best move, where one point is 1 % of win chance. Marks can come on top of it.

• Book move: an opening move found in the opening book or in enough master games. It counts as no loss.
• Best: loses at most 1 point. Several moves can be Best, not only the engine's first choice.
• Good: loses at most 3 points.
• Inaccuracy: loses at most 8 points.
• Mistake: loses at most 20 points.
• Blunder: loses more than 20 points.
• Brilliant (!!): the best move, after which the opponent's best reply wins at least two points of material more than the move itself did: a sacrifice that works, like 16.Qb8+ in the Opera Game of 1858.
• Great move (!): the best move when the second-best line of the same search is at least 15 points worse: the only good move.
• Missed chance: after an opponent move that lost at least 15 points, your own move loses at least 10, so the chance went by.

What should you look at first, and what can you ignore?

1. Accuracy and the counts of inaccuracies, mistakes and blunders for each side: a clean game and a game with one disaster look different here. How accuracy is calculated.
2. The evaluation graph. Click where it falls sharply: that is where the game turned.
3. Where you left theory. The review shows the last move of opening theory and where new territory starts.
4. Blunders, then mistakes. Each one shows a better move, the line your opponent could play and, when there is one, a reason such as "Hangs the knight", "Misses mate in 3" or "Throws away a winning position".

Ignore what has nothing to teach you: Book, Best and Good moves. Inaccuracies, a loss of 3 to 8 points, deserve a look only after the mistakes and blunders. Moves in a position that is already clearly won or lost cost few points, so their labels weigh less. And the accuracy number is a summary, not a rating of you: the reasons tell you what to do.

How do you turn a review into one thing to practise?

Read the reasons under your mistakes and blunders and pick the one that repeats. If you hang pieces, make a habit of asking before each move what it leaves undefended. If you throw away won positions, slow down when you are ahead. If the errors cluster in one phase, opening, middlegame or endgame, study that one. Write it as one sentence and read it before your next game.

Then use the review's practice mode: choose White or Black and it sets the position before each of your mistakes and blunders, and you look for a better move on the board. A move that is Best or Good counts as right, the move from your game does not, you get a hint after two tries and "Show the solution" shows the best line.

Want to try it on your own game? Review one of your games and read it with this guide beside you.