Tempo — what it means in chess
A single unit of time; gaining a tempo means developing or threatening while the opponent must respond.
A single unit of time; gaining a tempo means developing or threatening while the opponent must respond.
A tempo is one unit of chess time — a single move's worth of progress. Gaining a tempo means your move did double work, usually by developing with a threat that forces the opponent to spend their move responding without progress of their own. Losing one means the reverse: a piece that moves twice to reach a square it could have reached once has donated a stride to the other side.
[[board startfen="rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1" pgn="1. e4 d5 2. exd5 Qxd5 3. Nc3" caption="The textbook tempo gain: the knight develops with a threat, and the queen must move again." notes="The opening position. e4 — the standard start. d5 — the Scandinavian: Black challenges the center on move one. exd5 — the pawn is exchanged. Qxd5 — and here is the cost of the setup: the queen recaptures, entering the game before any minor piece. Nc3 — the tempo in its purest form. White develops a piece to its best square and attacks the queen in the same motion. Black's reply must be another queen move — so White develops twice while Black develops nothing."]]
Tempo is the currency of the opening — development is measured in it — but it never stops mattering: the zwischenzug is a stolen tempo in the middle of a sequence, and the initiative is what a saved-up pile of tempi buys. In the deepest endgames the account inverts, and the obligation to move becomes a burden — but that is zugzwang's page, and the exception that proves how much the clock inside the position matters.
The Endgame Society glossary defines more than 240 chess terms — rules, notation, tactics, strategy, pawn structures, endgames, and openings — in language a beginner can act on rather than dictionary shorthand.