Two big tap halves for a board on the table. Presets from 1+0 to 90+30, time odds, increment, delay and Bronstein, move counters and a flag.
A chess clock is two countdown timers that never run at the same time: when you finish your move you press your side, your timer stops and your opponent's timer starts. This page does the same on a phone, tablet or laptop. Put the device between the players. In portrait the top half is turned upside down so the player across the table reads it the right way up; in landscape the halves sit side by side. The first tap starts the other player's clock and does not count as a move, just as Black starts White's clock on a physical clock. After that each tap by the player on the move counts one move, passes the turn and adds any increment. A tap from the player who is not on the move is ignored, so a nudge cannot steal time. The clock keeps time from your device's timestamps, not from counting ticks, so a throttled background tab still shows the right time when you come back.
Three kinds of extra time exist, and they differ. Increment, often called Fischer, adds a fixed number of seconds to your clock after you complete each move. Here the increment is granted from move one, as in US Chess rule 16B2 and on DGT clocks: with 3+2 each clock shows 3:02 when that player's first turn starts, and a move that takes 10 seconds then leaves 3 minutes 2 seconds less 10 seconds plus 2 seconds. Your clock can grow past its start. A player who runs out of time before pressing gets no increment. Simple delay, also called US delay, makes the clock wait: with a 5 second delay your main time does not move for the first 5 seconds of your turn, then counts down. Unused delay is lost, so your main time never goes up. Bronstein delay counts down at once and, when you move, adds back the time you used, up to the delay. A 3 second move with a 5 second Bronstein delay returns all 3 seconds; a 12 second move returns 5. The US Chess Federation describes simple and Bronstein delay as equivalent in effect, differing in how the clock shows the time. In this tool Bronstein is equivalent to simple delay: the shown time counts down at once, but the flag falls only after your main time plus the delay is used, never earlier. These rules follow the FIDE Laws of Chess, Article 6, and the US Chess rule book on delay.
The seven presets cover common controls: 1+0 bullet, 3+2, 5+0 and 10+0 blitz (FIDE counts a fixed 10 minutes or less as blitz), 15+10 rapid, 30+0 for a long evening game and 90+30 for a classical game. The first number is minutes for each side and the number after the plus is the increment in seconds per move. Open Custom time, increment and delay to type any time from 1 second up to 99 hours for each player separately. Different times give time odds: a strong player can take 1 minute against a weaker player's 5 minutes. The increment or delay is the same for both sides. Changing the setup resets the clock, because changing time in the middle of a game would be unfair. The tool does not track time controls with several stages, such as 40 moves in 90 minutes followed by 30 minutes more.
When a player's time reaches zero the clock stops, that half shows Time is up, and the other player is shown as the winner on time. Under the FIDE Laws a player whose flag falls loses unless the opponent cannot possibly checkmate with any legal sequence of moves, for example with a bare king; this tool declares the winner on time and does not judge material, so check that yourself. Under 20 seconds the clock shows tenths of a second and turns red as a warning, and an optional beep sounds each second in the last 10 seconds, off by default. Press Space or the Pause button to stop both clocks, for example to call an arbiter; time on the move is kept and a simple delay already used stays used. On a keyboard, A taps the bottom player's half and L taps the top one; the keys are ignored while you type in a field. Where the browser supports it, the screen stays on while the clock runs. Your times and settings stay on this device; only the fact that a clock was started is counted, without times, moves or settings.
Each player starts with 3 minutes and gets 2 seconds added after every move. A player who takes 10 seconds on a move ends up with 3 minutes 2 seconds less 10 seconds plus 2 seconds (the first increment is granted when the first turn starts), so a game of 40 quick moves can last well past 6 minutes in total.
Increment adds seconds to your clock after your move, so your time can grow. Delay only waits: with a 5 second delay the clock does not run for the first 5 seconds of your turn, and any unused delay is lost, so your time never grows. Bronstein delay gives back the time you used, up to the delay.
The player with the Black pieces taps their half first. That starts White's clock and is not counted as a move. White then moves and taps their own half, which starts Black's clock, and from then on each tap counts one move.
Yes. Open Custom time, increment and delay and give each player their own minutes and seconds, for example 10 minutes against 3 minutes as time odds. The increment or delay is the same for both sides, and changing the time resets the clock.
The clock stops, your half shows Time is up and the other player is declared the winner on time. The FIDE Laws make an exception if the opponent has no way to checkmate, such as a lone king, and the tool does not check that, so settle it between you.
Yes, because it reads the device clock on every redraw instead of counting ticks. A 2 minute gap in a background tab is counted as 2 minutes of the player on the move. The screen also stays on while the clock runs on browsers that support wake lock.