Chess Clock

A chess clock is two clocks that run one at a time: after a move you press your button, your clock stops and your opponent's starts. The time control is the amount of time each player has and how it grows. This page offers the standard categories with common presets and a custom option.

The notation 3+2 means three minutes each, plus two seconds added after every move.

An increment (also called Fischer increment) adds a fixed number of seconds to your clock after each move you make, so a player with little time left can keep playing quickly without losing on time. It rewards fast, accurate play in the endgame and prevents the "flagging" of a winning position. A delay (Bronstein or US-style) instead waits a few seconds before your clock starts running on each move; the effect is similar but your time can never increase. Most online play and modern tournaments use increment, which is what this clock implements. Set it to zero for a pure sudden-death control.

• Place the device between the players, with each player's clock on their side. The large tap areas mean the whole half of the screen is the button.
• Press with the same hand that moved the piece; it is the rule in tournaments and it stops disputes.
• The space bar switches clocks on a keyboard, which is handy when a laptop sits beside the board.
• When a clock reaches zero it shows a flag and the sound plays. Whether a flag is a loss depends on the position (a player with insufficient mating material cannot win on time); the clock simply reports the fact.
• Pause is for disturbances and arbiter calls, not for thinking. Agree beforehand who may press it.

Any two-player game with alternating turns works with this clock: draughts, Go, Scrabble, backgammon. For three or more players use the board game timer, which gives each player a fixed time per turn. For a single shared countdown over a round, the timer is enough, and the stopwatch records how long a whole game took.