Chess clock online
Put the phone between the players, choose the time control and tap your own half to end your move. The top half is upside down so your opponent can read it.
How it is calculated
How the online chess clock works
The chess clock shows each player’s remaining time. Once you have made your move, tap your own half: your clock stops and your opponent’s starts. On a phone, the device lies between the players, so the top half is rotated by 180 degrees. In landscape on a tablet or laptop, both clocks sit side by side.
Only the remaining times and the moment the current move began are stored; the display is recalculated from the current time on every frame. That is why the clock does not fall behind when the browser throttles a background tab, and why it keeps running after an accidental reload.
Start a game in three steps
- Tap a preset (e.g. 3+2 for blitz) or enter the time, increment and timing mode.
- The player with Black taps their half – this starts White’s clock, just like over the board.
- After every move, tap your own half. “Pause” stops the running clock, “Reset” starts over.
Increment, Bronstein and delay
- Increment (Fischer): the set number of seconds is added after every move, including the first. Your remaining time can therefore rise above the starting time. This is the standard mode under the FIDE Laws of Chess.
- Bronstein delay: you get back the time you used on the move, but no more than the set seconds. Your time never rises above what it was before the move.
- Simple delay (US delay): the clock only starts counting down once the delay has passed. Move quickly and you lose no time at all. This mode is common in US Chess events.
Example 3+2: each player has 3 minutes. White spends 10 seconds on the first move: 3:00 − 0:10 + 0:02 = 2:52. If Black replies after 1 second, Black’s clock shows 3:00 − 0:01 + 0:02 = 3:01.
Common time controls
- Bullet and blitz: 1+0, 3+2 or 5+3 – the game is over in a few minutes.
- Rapid: 10+5 or 15+10. Under FIDE rules a game is rapid if the time per player for 60 moves (base time + 60 × increment) is more than 10 and less than 60 minutes.
- Classical: 90+30, i.e. 90 minutes plus 30 seconds per move – the standard time control of many tournaments.
Move counter, flag fall and sound
Below each clock you see the number of completed moves. Under ten seconds the clock shows tenths. When a player’s time runs out, their half turns red, the clock stops and – if enabled – an alarm sounds, which is scheduled in advance on the browser’s audio clock. Whether that loses the game depends on the rules (can the opponent still checkmate?); the clock does not decide that.
Tips
- Switch to full screen so nothing else distracts you. While the clock is running, most phones keep the screen on.
- Play on a laptop with the keyboard: the left hand presses A, S, D or Left Shift, the right hand J, K, L or Enter. The space bar always ends the move of whichever side is running.
- Tapping the half that is not running is ignored – a double tap will not switch the clock back.
Around the board: decide who plays White with flip a coin, plan a rapid or blitz event with the tournament bracket generator, and time your analysis with the online stopwatch.
Frequently asked questions
Who starts the chess clock?
Just like over the board, the player with Black starts White’s clock: they tap their own half, and then the opponent’s time starts running.
What does 3+2 mean on a chess clock?
3 minutes of base time per player plus 2 seconds added (increment) after every move. The first number is minutes, the second is seconds.
What is the difference between increment and delay?
With an increment (Fischer), fixed seconds are added after every move, so your time can grow. With a delay, the clock only starts after the set time (US delay), or at most the time you used is given back (Bronstein) – your time never grows.
Does the chess clock keep running if I reload the page?
Yes. Remaining times, move counts and the start of the current move are stored in your browser (localStorage), so the clock shows the correct time after a reload. The alarm sound is only re-enabled after the next tap.
Can I pause the chess clock?
Yes, with “Pause” or the P key. The time already used on the current move is kept, including a partly used delay.
Does the chess clock work offline?
Once the page has loaded, the clock runs entirely in your browser; no data is sent to a server.
Can I use an online chess clock in tournaments?
For club nights, training and casual games, yes. Rated tournaments usually require approved tournament clocks set by the organiser; the FIDE rules on the clock apply here in spirit.
Sources and legal basis
- FIDE Handbook E.I.01A: FIDE Laws of Chess, Article 6: The chessclock
- Time control – increment, Bronstein and simple delay
- MDN: Page Visibility API
As of:
Related tools
- Online score keeperFree online score keeper and score counter for board and card games: rounds, running totals, rankings, target score and undo. Saved locally in your browser.
- Tournament bracket and round robin generatorFree tournament bracket generator and round robin scheduler: byes, seeding, multiple courts, scores, standings table and a printable view. No sign-up.
- Flip a coin: heads or tails?Flip a coin online: heads or tails, 1 to 100 coins per toss, live stats with share and longest streak. Fair cryptographic randomness, no sign-up.
- Roll dice online: d6, d20 and moreOnline dice roller: roll 1–10 dice with 4, 6, 8, 10, 12 or 20 sides, d6 with dots, total, roll history and exact odds. Fair cryptographic randomness.
- Play the 2048 game onlinePlay 2048 free in your browser: swipe or use the arrow keys to merge tiles until you reach 2048. With best score, one-step undo and your game saved.
- Aim Trainer OnlineFree online aim trainer: hit 30 targets against the clock or as many as you can in 30 seconds. Three target sizes, accuracy and average time per target.