Chess Clock

A chess clock gives each player a separate countdown and runs only one at a time. After you move, you tap your side to stop your clock and start your opponent's. This page works that way on a phone, tablet or computer.

On a phone the buttons are large and the top clock is turned upside down so the player opposite can read it.

How to use this tool

1. Choose a time control from the list (1+0, 3+2, 5+0, 5+3, 10+0, 15+10 or 30+0) or select Custom and enter minutes per player and increment seconds.
2. To begin, the player who moves second taps their own side. That starts the clock of the player who moves first.
3. After each move, tap your side or press your key. Keys on the left half of the keyboard (Q, A, Z and so on) belong to Player 1, keys on the right half (P, L, M and so on) to Player 2, and Space presses for the side to move.
4. Use Pause to stop both clocks and Reset to start again with the chosen control.

Reading a time control

A control written 5+3 gives each player five minutes plus a three-second increment. With a Fischer increment, named after Bobby Fischer, those seconds are added to your clock after each move you make, so your time can grow when you move quickly. A control written 10+0 has no increment.

Bullet, blitz and rapid

FIDE, the international chess federation, treats games where each player has 10 minutes or less as blitz and longer games up to 60 minutes as rapid, counting the increment as if sixty moves are played. Online sites often call very short games, such as 1+0, bullet. Labels differ between organizations, so check your event's rules.

When time runs out

When a clock reaches zero, a flag appears on that side, a sound plays and both clocks stop. In real tournaments, what happens after a flag falls (for example when the opponent has too little material to win) is decided by the arbiter; this clock only shows that the time ran out.

Sound plays only after you have pressed something on the page once, and the device must not be muted.