Chess time controls explained
Chess time controls explained in a sentence: a time control sets how much time each player gets and how that time is topped up. Read one left to right. The number before the plus or bar is your base time in minutes, and the number after it is the seconds added or held back on every move. So 5+3 (also written 5|3) means five minutes each, plus three seconds per move. G/30 means game in thirty minutes, no bonus. G/30 d5 means game in thirty minutes with a five-second delay before your clock starts running each turn.
Everything else is a combination of those parts. Decode the notation and you can set any control on the chess clock on the front page in seconds, whether it came from a tournament flyer, a club noticeboard or an online lobby.
How to read the notation
Four formats cover almost everything you will meet.
- 5+3 or 5|3 — five minutes base, three seconds increment per move. Used online and on most digital clocks. The two symbols mean the same thing; the bar is just easier to read on a small screen.
- G/30 — “game in 30”. Each player has 30 minutes for the whole game. American clubs use this style.
- G/30 d5 — game in 30 with a five-second delay. The d is the giveaway: delay, not increment. Increment in the same style is written G/30 inc5, or G/30 +5.
- 40/90, SD/30 +30 — 40 moves in 90 minutes, then sudden death in 30 more minutes, with a 30-second increment running throughout. This is a multi-stage control, and it is the standard shape of serious over-the-board play.
A number written as a fraction, like 40/90, always means moves over minutes. A number after a plus is always seconds. A number after a d is always delay seconds.
The four building blocks
Base time. The starting number on your clock. Two minutes, thirty minutes, ninety minutes. This is the only part you must have; a control can be nothing but base time.
Increment. A fixed number of seconds added to your clock every move. Play a move in two seconds with a five-second increment and you finish the move three seconds richer than you started it. Increment can therefore grow your time, which is why it is the standard fix for scrambles decided by a mouse slip rather than a mistake. The mechanics are covered in the guide on what increment means in chess.
Delay. A countdown that runs before your main clock starts. With a five-second delay your clock sits still for five seconds each turn, then begins ticking. Delay never adds time: the best you can do is break even. Simple delay (the US style) freezes the main clock; Bronstein delay lets the clock run and then hands back whatever you used, up to the delay amount. Both leave you with the same number after the move, so they are mathematically equivalent and differ only in what the display does while you think. The delay versus increment comparison explains which one a given event will expect.
Extra stages. Instead of one lump of time, the game is cut into periods. Reach the move requirement of a stage and a new block of time is added to whatever you have left. In 40/90 followed by 30 minutes, a player who reaches move 40 with 12 minutes left starts the second stage with 42 minutes. Time carried over is never lost.
Increment starts when the flyer says it starts. “+30 from move 1” and “+30 from move 41” are different games. The 2024 Chess Olympiad used 90 minutes for 40 moves plus 30 minutes, with the 30-second increment from move one. The 2024 Candidates used 120 minutes for 40 moves plus 30 minutes, with the increment only from move 41 — so the first forty moves there were a hard 120 minutes with no cushion at all.
What sudden death means
Sudden death is any period where the rest of the game must be finished in the time remaining, however many moves that takes. In 40/90, SD/30, the SD/30 is that phase: no further block is coming, so if the game runs to move 120 you still have only those 30 minutes plus whatever increment you earn along the way. Older controls handed out a fresh block at every checkpoint, with anything unfinished adjourned and resumed another day.
A single-period control like G/30 is sudden death by definition. That is why almost every modern sudden-death control carries a delay or an increment: without one, a completely won endgame can be lost to the mechanics of moving pieces.
Chess time controls explained: a reference table
The last column is arithmetic, not a survey: the ceiling if both players burn every second, (base + bonus × moves) × 2, over 40 moves each, or 60 for the multi-stage rows that only reach a second stage after move 40. Delay counts in that sum even though it never lands on anybody's clock — a player who uses the full five seconds every move has still spent five seconds of the evening. Most games finish well short of these numbers.
| Notation | What it means | Category | Longest it can run |
|---|---|---|---|
| 1+0 | 1 minute, no bonus | Bullet online; blitz to FIDE | 2 minutes |
| 2+1 | 2 minutes, 1s increment | Bullet online; blitz to FIDE | 5 minutes 20 seconds |
| 3+0 | 3 minutes, no bonus | Blitz | 6 minutes |
| 3+2 | 3 minutes, 2s increment | Blitz | 8 minutes 40 seconds |
| 5+0 | 5 minutes, no bonus | Blitz | 10 minutes |
| 5+3 | 5 minutes, 3s increment | Blitz | 14 minutes |
| 10+0 | 10 minutes, no bonus | Rapid online; blitz to FIDE | 20 minutes |
| 15+10 | 15 minutes, 10s increment | Rapid | About 43 minutes |
| G/25 d5 | 25 minutes, 5s delay | Rapid | About 57 minutes |
| G/30 d5 | 30 minutes, 5s delay | Rapid; dual rated by US Chess | About 1 hour 7 minutes |
| G/60 d10 | 60 minutes, 10s delay | Standard to FIDE; regular rated by US Chess | About 2 hours 13 minutes |
| G/90 +30 | 90 minutes, 30s increment | Classical | 3 hours 40 minutes |
| 40/90, SD/30 +30 | 40 moves in 90 min, then 30 min, 30s increment throughout | Classical, multi-stage | 5 hours to move 60 |
| 40/120, SD/30 +30 from move 41 | 40 moves in 120 min, then 30 min with increment | Classical, multi-stage | About 5 hours 20 minutes to move 60 |
Online categories and FIDE categories are not the same system
Under the FIDE Laws of Chess, a game is blitz if the fixed time is 10 minutes or less, or if the allotted time plus 60 times any increment comes to 10 minutes or less. It is rapid if that figure is more than 10 minutes but less than 60. At 60 minutes and above the full standard laws apply, which is the band most players call classical. The Laws set out only those categories, so a one-minute game is simply the fast end of blitz there rather than a separate bullet class. The official FIDE time controls are set out in more detail elsewhere on the site.
Online servers use their own arithmetic. Lichess estimates a game's duration as base seconds plus 40 times the increment, then sorts it: 29 seconds or less is ultrabullet, up to 179 seconds is bullet, up to 479 is blitz, up to 1,499 is rapid, and 1,500 or more is classical. That is why 10+0 is rapid on Lichess but blitz to an arbiter, and why an online “classical” game of 25+0 — exactly 1,500 seconds — is only rapid under the Laws.
US Chess uses a third measure, adding the base minutes to the delay or increment seconds as if they were minutes. Roughly: 5 to 10 is blitz, 10 to 29 is quick, and 30 through 65 is rated as both quick and regular at once, with longer controls regular only. So G/30 d5 counts twice while G/60 d10 counts once. If you are deciding what to play rather than what to enter, the practical differences are laid out in blitz versus rapid versus classical.
Try a control before you commit to it
Notation clicks once you have felt the control. Open the clock on this site, tap a preset such as 3+2 or 15+10, and play a few moves. The web clock runs increment, simple delay, Bronstein delay, hourglass and two-stage tournament controls, so you can rehearse the exact 40/90, SD/30 +30 you will face on Saturday.
If you want a clock in your pocket at the board, the Chess Timer — Chess Clock app is a free download on the App Store and Google Play, with presets, a custom base time and Fischer increment, and it works offline. It gives you three start or pause actions before asking for a premium unlock, and it plays increment only — delay, Bronstein and multi-stage play stay here on the web clock.