A chess clock is two clocks in one case, with a button on top for each player. Only one clock runs at a time. When you’ve made your move you press your button, which stops your clock and starts your opponent’s. Each player has their own pool of time for the whole game, and if yours runs out first you usually lose. A time control like 5+3 says how much: five minutes each, plus three seconds added after every move.
No clock to hand? Our free chess clock runs on a phone or tablet laid flat beside the board.
Reading a time control
| Written | Means |
|---|---|
| 5+0 or 5|0 | 5 minutes each for the whole game, nothing added. Also called sudden death. |
| 3+2 or 3|2 | 3 minutes each, plus 2 seconds added after every move. |
| 15+10 | 15 minutes each, plus 10 seconds a move. |
| 90/40 + 30, 30 s from move 1 | 90 minutes for the first 40 moves, then 30 more minutes for the rest of the game, with 30 seconds added every move from the first. This is the usual FIDE time control for classical (slow) games. |
| G/30;d5 | US style: game in 30 minutes with a 5-second delay (see delay, below). |
The first number is always minutes and the second is always seconds.
Blitz, rapid and classical
The FIDE Laws sort games by the time each player has. To count an increment fairly, they assume a game of 60 moves: add 60 times the increment to the starting time. Sixty moves of 2 seconds is 2 minutes, so 3+2 counts as 5 minutes.
| Kind | Time each (starting time + 60 × increment) | Examples |
|---|---|---|
| Blitz | 10 minutes or less | 3+0, 3+2, 5+0, 5+3, 10+0 |
| Rapid | More than 10 minutes and less than 60 | 10+5, 15+10, 25+10, 30+0 |
| Standard (also called classical) | 60 minutes or more | 45+15, 60+30, 90+30, 90/40 + 30, 30 s |
Bullet isn’t a FIDE category. It’s what chess websites call their fastest games, under about three minutes each. Websites draw their own lines in general, which is why 10+0 is blitz under the FIDE Laws but “rapid” on most sites.
Increment, delay and Bronstein delay
Sudden death has a problem: in a won position, you can still lose if you run out of time. Extra time per move fixes that, and there are three ways to give it.
- Increment (also called Fischer, after Bobby Fischer, who invented it): a set number of seconds is added to your clock every move. Move fast and your time builds up.
- Simple delay (also called US delay, common in American events): when your turn starts, your clock waits for the delay before it begins to count down. Any delay you don’t use is lost.
- Bronstein delay (after the grandmaster David Bronstein): your clock counts down straight away, but when you press it you get back the time you used, up to the delay.
Here’s each one with 10 seconds on the clock, 5 seconds extra per move:
| Mode | Left after a 3-second move | Left after an 8-second move |
|---|---|---|
| Sudden death | 7 s | 2 s |
| Increment | 12 s (10 − 3 + 5) | 7 s (10 − 8 + 5) |
| Simple delay | 10 s (the clock never moved) | 7 s (it moved for 3 s) |
| Bronstein delay | 10 s (3 s given back) | 7 s (5 s given back) |
Simple delay and Bronstein delay always leave you with the same time after a move; only the display while you think is different. With either kind of delay you can never end a move with more time than you started it with. Increment is the only one where time can grow, which is why a long game with an increment can run well past its nominal length.
One detail differs between clocks: the glossary of the FIDE Laws describes the extra time as given before each move, and some digital clocks add it at the start of your turn. Our clock, like most chess websites, adds it as you finish your move. Either way you get it once per move.
The clock rules at a club or tournament
From the FIDE Laws of Chess, the ones you’re most likely to need:
- White’s clock starts the game. At the start time, White’s clock is started. At a tournament the arbiter announces it; at a club the player with the black pieces usually presses to start it.
- Move, then press, with the same hand. You must press your clock with the hand you moved with. Your move is made when you let go of the piece on its new square; pressing the clock finishes your turn.
- Offer a draw at the right moment: after you’ve made your move and before you press the clock.
- Time running out. If your time runs out, you lose, unless your opponent couldn’t checkmate you with any series of legal moves. Then it’s a draw.
- Writing the moves down. In standard games you must keep score; in rapid and blitz you don’t have to. Our notation lesson shows how.
Events often add their own rules on top, so read the entry form or ask the arbiter.
Why it’s called “flagging”
Old analogue chess clocks have a small red flag near the 12 on each face. As the minute hand nears the hour it lifts the flag, and on the hour the flag drops. So running out of time is a “flag fall”, and beating someone on time is “flagging” them. Digital clocks just show a flag symbol or zeros, but the words stuck.
Which time control for a game at home?
- Learning, or playing children: no clock, or something long like 30+0, so nobody feels rushed.
- A relaxed evening game: 15+10. Enough time to think, and the 10 seconds a move stops anyone losing a won game on time.
- Quick games to play several in a row: 5+3 or 3+2.
- A stronger player against a newer one: give the stronger player less time. A handicap of half the time, or 5 minutes against 15, keeps it a fair fight.
Common questions
What does 3+2 mean in chess?
Is a 10-minute game blitz or rapid?
What is the difference between increment and delay?
What happens if your time runs out in chess?
Who starts the chess clock?
Sources
- FIDE Laws of Chess, taking effect from 1 January 2023: Article 6 (the chessclock), Article 9.1 (draw offers), Appendix A (rapid chess), Appendix B (blitz) and the glossary (cumulative and delay modes). FIDE Handbook. link. Checked 11/11/2026.
- The worked figures in the increment and delay table were checked against our own chess clock, which runs the same sums.