Clock log

Chess Clock

A two-player chess clock that keeps a record of every move. Increment or delay, extra time at a move number, a spectator window for a second screen and a printable game record when the game ends.

New game

Pick the time control, enter the players and start. Every clock press is recorded as proof of the game.

Time control
Players
Game details (shown on the record)

How to run a game

Choose a time control, type the two players' names and press Start game. White's clock starts when you press Start. After each move, the player taps their own lit clock (or you press the spacebar) and the other clock begins. Every press is written into a log with the time used, the time left and the time of day.

Time controls

Pick a ready-made control such as 3+2 or 90+30, or type your own. The number after the plus is the seconds given per move. You can also add extra time at a move number, for example 30 more minutes after move 40, and you can give White and Black different starting times for a handicap game.

  • Increment: the seconds are added to a player's clock after every move.
  • Bronstein delay: after each move the player gets back the time they used, but never more than the delay.
  • Simple delay: the clock waits for the delay seconds at the start of each turn before it starts counting down.

Pausing, undoing and fixing time

Pause stops both clocks. If a player presses by mistake, Undo last press puts the time and the turn back. For a clock mistake, an arbiter can add or take away time with Adjust time; each change is saved in the log together with the reason.

Spectator window

Open the spectator window and drag it to a projector or second monitor. It shows both clocks in large digits, the players' flags and ratings, and the full log underneath. It updates by itself every time a move is played, so the audience always sees the same game that the arbiter is running.

Game record and tournament book

When the game ends, record the result and how it ended. You get a printable game record with the players, the time control, a summary for each player, a chart of the time left after every move, the complete clock log and signature lines for both players and the arbiter. Finished games stay in your list, so after a round you can print one book with the results table and every game, or download all clock presses as a spreadsheet file. Games are kept on your device; use the backup file to move them to another computer.

Expert Answers

Frequently Asked Questions

Top questions about the Chess Clock.

Increment is a number of seconds added back to a player's clock every time they finish a move. In a 3+2 game each player starts with 3 minutes and gains 2 seconds after every move, so a player with a winning position is not beaten only by the clock.
With increment the seconds are added after your move, so you can save them up. With a delay the clock simply waits at the start of your turn and only then begins to count down, so unused delay seconds are lost. Bronstein delay sits in between: after your move you get back the time you actually used, up to the delay.
The clock stops, that player's panel turns dark and a box asks you to record the result. Normally the player who ran out of time loses, but if the other player could not possibly win by any legal moves the game is a draw, so the clock lets you choose.
Yes. Press Undo last press (or the U key) and the clock goes back to how it was before that press, with the right player to move. The log notes that the press was undone. If an arbiter changed the time after the press, undo is not offered, so nothing is lost by accident.
Press Spectator window, then drag the new window to the projector or the second monitor. It shows both clocks in big digits with the log underneath and updates by itself. Keep it on the same browser and the same computer as the clock.
The game is saved after every press. When you open the page again it brings the game back with the clock paused, so you can check the time and press Resume. The pause is written in the log.
It keeps an exact timed record of every press, which is what many organisers want for their own results. Whether a software clock is allowed in a rated event is decided by the organiser, and some events only allow approved clocks, so please check with them first.
Only on your own device, in your browser. Nothing is sent to a server. Use the backup file in the games list to keep a copy or to move your games to another computer.
Snooker Score TrackerTrack snooker frames, breaks and fouls for 2-6 players in real time, with photos and an audience display.