Chess annotation symbols

When annotating chess games, commentators frequently use widely recognized annotation symbols. Question marks and exclamation points that denote a move as bad or good are ubiquitous in chess literature. Some publications intended for an international audience, such as the Chess Informant, have a wide range of additional symbols that transcend language barriers.

The common symbols for evaluating the merits of a move are "??", "?", "?!", "!?", "!", and "!!". The chosen symbol is appended to the text describing the move (e.g. Re7? or Kh1!?); see Algebraic chess notation.

Use of these annotation symbols is subjective, as different annotators use the same symbols differently or for a different reason.

Move evaluation symbols, by decreasing severity or increasing effectiveness of the move:

The double question mark "??" indicates a blunder, a critically bad mistake. Typical moves that receive double question marks are those that overlook a tactic that wins substantial material or overlook a checkmate. A "??"-worthy move may result in an immediately lost position, turn a won position into a draw, lose an important piece or otherwise severely worsen the player's position. Though more common among weaker players, blunders occur at all levels of play.

A single question mark "?" indicates that the annotator thinks that the move is a mistake and should not have been played. Mistakes often lead to loss of tempo, material, or otherwise a worsening of the player's position. The nature of a mistake may be more strategic than tactical; in some cases, the move receiving a question mark may be one for which it is difficult to find a refutation. A move that overlooks a forthcoming brilliant combination from the opponent would rarely receive more than one question mark, for example. The symbol can also be used for a move that overlooks a far stronger move.

A question mark followed by an exclamation mark "?!" usually indicates that the annotator believes the move to be dubious or questionable but to possibly have merits or be difficult to refute. The "?!" may also indicate that the annotator believes the move is weak, of doubtful value, or deserves criticism but not bad enough to warrant a "?". On certain Internet chess servers, such as Chess.com and Lichess, this kind of move is marked as an "inaccuracy", denoting a weak move, appearing more regularly than with most annotators. A sacrifice leading to a dangerous attack that the opponent should be able to defend against if they play well may receive a "?!". Alternatively, this may denote a move that is objectively bad but sets up an attractive trap.

Similar to "?!" (see above), an exclamation mark followed by a question mark "!?" is one of the most controversial symbols. Different sources have slightly varying definitions, such as "interesting, but perhaps not the best move", "move deserving attention", "speculative move", "enterprising move" or "risky move". Usually it indicates that the move leads to exciting or wild play but that the objective evaluation of the move is unclear. It is also often used when a player sets a cunning trap in a lost position. Typical moves receiving a "!?" are those involving speculative sacrifices or dangerous attacks that might turn out to be unsound.