Increment, delay and Bronstein compared
| Method | When time changes | Can the bank grow? |
|---|---|---|
| Increment | Seconds are added after the move | Yes |
| Simple delay | Main time falls after protected seconds | No |
| Bronstein | Used time is returned up to a limit | No |
Increment
With increment, the configured number of seconds is added after a completed move. If you move faster than the increment, your displayed bank can grow. This is often called Fischer increment. On this site, choose Increment and watch the bonus appear immediately after each press.
Delay
With simple delay, the main time does not decrease until the delay period has elapsed. Unused delay is not added to the bank. Some physical clocks show the delay counting separately; others keep the main display still, which can look confusing if you have not tested the mode.
Bronstein timing
Bronstein timing returns up to the configured allowance after the move, but never more than the time actually spent. It resembles delay in practical effect while the display may behave differently. Always name the exact mode instead of using 'bonus' as a catch-all.
Source for the factual guidance above: FIDE Laws of Chess.
A side-by-side ten-second example
Assume the main display begins at 1:00 and the bonus is five seconds. With increment, a move that takes three seconds leaves about 1:02 after the press: three seconds were spent and five were added. With simple delay, the same move can leave 1:00 because it finished inside the protected window, but the unused two seconds disappear. With Bronstein timing, the clock may deduct the spent time and return up to five seconds after the move. The final numbers can resemble delay even though the accounting and display sequence differ.
How each mode changes strategy
Increment can rebuild the displayed bank when moves are completed faster than the bonus. That makes long technical endings more playable, but only if a player continues making legal moves. Simple delay prevents an immediate drain on routine actions without allowing the bank to grow. Bronstein timing similarly limits the net cost of a quick move. Near zero, these differences are decisive: knowing that the main bank can grow is different from knowing only that its decrease can be temporarily protected.
How to verify an unfamiliar clock
Set one minute with a five-second bonus and watch a complete turn. Make one move inside three seconds and another after seven seconds. Record the display before the turn, immediately before the press, and immediately after. Increment should add a fixed five seconds after each press. Simple delay should protect the opening portion but add nothing. Bronstein should return no more than the time actually used, capped at five seconds. If the device manual uses a broad term such as bonus, trust the observed sequence and documented mode definition rather than the label alone.
Once the accounting method is clear, verify it with the chess clock setup procedure.
Common questions
Is chess increment the same as delay?
No. Increment adds time after a completed move. Simple delay protects the first seconds of a turn before the main bank starts falling.
Can increment make the displayed time increase?
Yes. If a player moves faster than the increment, the added seconds can leave more time than before that move.
Does unused delay carry over?
No. Any protected delay time left when the player presses the clock disappears; it is not added to the main time bank.
Is Bronstein timing the same as simple delay?
No. Bronstein timing returns up to a set amount of time after the move, while simple delay waits before reducing the main bank. They can have a similar practical effect but may display time differently.
Primary references & further reading
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