A chess clock online, for one phone and two players
A chess clock has two timers, one for each player, and only one runs at a time. When you finish your move you press the clock: yours stops and your opponent's starts. If your time runs out first, your flag falls. This online chess clock works on any phone, tablet or computer. Lay the phone flat between you, turn on face to face so the top player can read their time, and tap anywhere on your own half to end your move.
Time controls: what 3+2 or 15+10 means
A time control like 3+2 gives each player 3 minutes for the whole game plus 2 seconds per move. The presets cover common blitz and rapid settings, and Custom lets you enter any time from a quarter of a minute up to 10 hours, with 0 to 60 seconds per move.
| Preset | Time | Per move | FIDE type |
|---|---|---|---|
| 1+0 | 1 minute | none | blitz |
| 3+2 | 3 minutes | 2 seconds | blitz |
| 5+0 | 5 minutes | none | blitz |
| 10+0 | 10 minutes | none | blitz |
| 15+10 | 15 minutes | 10 seconds | rapid |
| 30+0 | 30 minutes | none | rapid |
The FIDE Laws of Chess define a blitz game as one where each player has 10 minutes or less, or where the time plus 60 times the increment is 10 minutes or less (Appendix B.1). A rapid game has more than 10 and less than 60 minutes by the same count (Appendix A.1). So 15+10 counts as rapid: 15 minutes plus 60 times 10 seconds is 25 minutes. And 3+2 counts as 5 minutes, which is blitz.
Increment (Fischer) and delay (Bronstein)
The clock offers the two ways to give extra time per move that the FIDE Laws of Chess (in force since 1 January 2023) describe. It follows their wording exactly:
- Increment, Fischer mode: the glossary calls this the cumulative mode, where a player receives an extra amount of time prior to each move, added from the start. So the clock adds the increment when your turn begins, including your first move. In a 3+2 game, White's clock shows 3:02 as soon as it starts. Seconds you do not use stay on your clock and add up.
- Delay, Bronstein mode: Article 6.3.2 and the glossary give each player a fixed extra time with every move. Your main thinking time only starts to count down after the fixed extra time has run out. If you press the clock before that, your main time does not change. Unused delay time is not saved for later, so your clock never shows more than you started with.
While a delay runs, your half shows the delay seconds that are left, and your main time stays still until they are used up.
When the time runs out
When a player's time reaches zero, the clock stops and marks that player's half. Under Article 6.9 of the FIDE Laws, a player who does not complete the moves in time loses the game, unless the opponent cannot checkmate the king by any series of legal moves, in which case the game is a draw. The clock cannot see the board, so you decide that part yourselves. Below 10 seconds the time turns red and shows tenths of a second.
How to use the chess clock
- 1Pick a preset or enter your own minutes and seconds per move, and choose increment or delay.
- 2The player with the black pieces taps their half (or presses Space) to start White's clock.
- 3After each move, tap your own half. Pause with the button or the P key, and press Reset for a new game.
For other games that need a timer, the online timer counts down any time, and the coin flip decides who plays White.
Frequently asked questions
How do I use this chess clock on my phone?
Put the phone flat between the players. The player with the black pieces taps their half to start White's clock. After each move, tap anywhere on your own half to stop your clock and start your opponent's. The top half is turned around so both of you can read your own time.
What does 3+2 mean?
The first number is the time for each player in minutes, the second the increment in seconds. In a 3+2 game each player starts with 3 minutes and gets 2 extra seconds for every move.
What is the difference between increment and delay?
With an increment (Fischer mode) the extra seconds are added to your time before each move, so time you do not use builds up. With a delay (Bronstein mode) your main time only starts to run after the fixed extra time has passed, and unused delay time is not saved. The glossary of the FIDE Laws of Chess defines both, and Article 6.3.2 describes the delay mode.
When is a game blitz and when is it rapid?
Under the FIDE Laws, a game is blitz when each player has 10 minutes or less, counting the time plus 60 times the increment. It is rapid when that total is more than 10 and less than 60 minutes. The clock shows which one your setting is.
Can I pause the clock?
Yes. Press Pause or the P key. Both clocks stop, and Resume continues with the same player. Press Reset to set both clocks back to the start time.
Does the clock keep the screen on?
Yes, where your browser supports it. While a game runs, the clock asks the browser to keep the screen awake, and lets it sleep again when you pause or the game ends.