Short answer: 15+10 means each player starts with 15 minutes on the clock and gets 10 extra seconds added back after every move they make. The first number is the base time in minutes, the second is the increment in seconds. It is one of the most popular rapid controls in chess, and it is the time control of the FIDE World Rapid Championship. Below you will see exactly how those 10 seconds add up, how long a 15+10 game really takes, and how many rounds you can fit into one evening.
15+10 means each player starts with 15 minutes and gains 10 seconds back after every move they make. The first number is base time in minutes, the second is the increment in seconds.
15+10, 15/10, 15 | 10 and 15:10 are all the same control. A 40 move game earns each player an extra 6 minutes 40 seconds. It is a rapid control, and a full game usually takes 30 to 45 minutes.
How the 10 Seconds Add Up
Every chess time control is written the same way: base time, then increment. With 15+10 you start on 15:00, and the moment you finish a move and press your clock, 10 seconds go back onto it. You can never lose those seconds once they are added, so a player who moves quickly can finish with more time than they started with.
| Moves Played | Seconds Earned | Most Time You Can Use |
|---|---|---|
| 20 | 3 min 20 sec | 18 min 20 sec |
| 40 | 6 min 40 sec | 21 min 40 sec |
| 60 | 10 min | 25 min |
| 80 | 13 min 20 sec | 28 min 20 sec |
That last column is per player, so double it for the longest a game can run. The increment is also why 15+10 feels so much calmer than plain 15 minutes: in a long endgame you always have at least 10 seconds for every move, so nobody loses a won position just because the clock ran out while they were tidying up.
15+10 is the over-the-board way of writing it, 15 | 10 is how Chess.com and Lichess show it, and people also type 15/10 or 15:10. All four mean 15 minutes plus 10 seconds a move. There is no hidden difference in the symbol.
Is 15+10 Rapid or Blitz?
15+10 is rapid everywhere you play it. FIDE classes a game by the time each player gets for 60 moves: base time plus 60 increments. For 15+10 that is 15 minutes plus 10 minutes, so 25 minutes each, well inside the rapid band of more than 10 and less than 60 minutes. Chess.com and Lichess estimate using 40 moves instead (15 minutes plus 40 times 10 seconds, about 21 minutes 40 seconds) and both file that under rapid too.
If you want a faster rapid game, 10+5 is the next step down. If you want to know where each category starts and stops, see bullet vs blitz vs rapid.
Set 15+10 once and ChessHost runs every round for you.
Start a free eventHow Long Is a 15+10 Game?
Most 15+10 games between club players finish in 30 to 45 minutes. A typical game lasts around 40 moves, which gives each player a maximum of 21 minutes 40 seconds, so the longest a 40 move game can run is a little over 43 minutes. Quick wins end sooner, and long endgames of 70 or 80 moves can push past 50 minutes.
A 15+10 Game in Real Minutes
For every other control, from bullet to classical, see how long a chess game takes.
Why 15+10 Is So Popular
- It is the championship rapid control. The FIDE World Rapid Championship is played at 15+10, so it has real prestige.
- It is a default pool online. Chess.com and Lichess both offer 15 | 10 as a one-tap rapid game.
- It is long enough to think. Beginners get time to look for their opponent's threats instead of just reacting.
- It is short enough for an evening. You can play several games in a night, which a classical game would never allow.
Running an Event at 15+10
If you are the organiser, the time control decides how many rounds fit. Plan on about 50 minutes per round once you allow for slow finishers, entering results and drawing the next round.
| Session Length | Rounds at 15+10 | Good For |
|---|---|---|
| 2 hours | 2 | A short club night |
| 3 hours | 3, maybe 4 with a tight schedule | A standard evening event |
| 5 hours | 5 | A Saturday afternoon Swiss for up to about 30 players |
| 7 hours | 7 | A full day with a lunch break |
Not sure how many rounds your player count needs? The free Swiss rounds calculator tells you, and the tournament duration calculator turns rounds into a finishing time. When you are ready to run it, free chess tournament software like ChessHost pairs every round and keeps the standings while you watch the clocks.
Frequently Asked Questions
What does 15+10 mean in chess?
Each player starts with 15 minutes and gains 10 seconds after every move. The first number is the base time in minutes, the second is the increment in seconds added back each move.
Is 15/10 the same as 15+10?
Yes. 15/10, 15+10, 15 | 10 and 15:10 all describe the same control: 15 minutes base plus a 10 second increment per move. The symbol is just a different way of writing it.
Is 15+10 rapid or blitz?
15+10 is rapid. FIDE counts base time plus 60 increments, which is 25 minutes per player for 15+10, inside the rapid band. Chess.com and Lichess also list 15+10 as rapid.
How long does a 15+10 chess game take?
Most 15+10 games take 30 to 45 minutes. A 40 move game gives each player at most 21 minutes 40 seconds, so the longest a 40 move game can run is a little over 43 minutes.
How many rounds of 15+10 fit in an evening?
Plan on about 50 minutes per round including results and pairing. That gives 3 rounds in a 3 hour evening, or 4 on a tight schedule, and 5 rounds in a 5 hour afternoon.
What time control is the World Rapid Championship?
The FIDE World Rapid Championship is played at 15 minutes plus 10 seconds per move, which is one reason 15+10 is the best known rapid control.
Know Your Clock? Now Run the Event
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