Updated November 2, 2026.

Three labels that change the game

Increment adds a specified amount of time for each move. Simple delay gives a waiting period before the main time starts falling. Bronstein delay displays the accounting differently, refunding time used up to the delay allowance. Delay does not let you bank unused seconds in the way increment can.

Before setting a clock, copy the event’s time control exactly. A plus sign in an online description is not enough information to guess the device preset. Check the main time, increment or delay, any additional periods and whether a move count is involved. Ask the organizer when the wording is unclear.

Work through a neutral example

To compare a single turn, assume the display has already reached 60 seconds at its start and the allowance is five seconds. With a five-second increment added after that turn, spending two seconds leads to 63 seconds. Spending eight seconds leads to 57 seconds. The example isolates one turn; initial increment handling depends on the clock and rules.

With a five-second simple delay, a two-second move leaves the main time at 60 seconds, while an eight-second move leaves 57. With Bronstein’s accounting, the main display may count down immediately and refund up to five seconds when you finish. The net charge is still zero for the two-second move and three seconds for the eight-second move.

Why the display can look different

Two clocks using delay can appear to behave differently during a move. One may show the delay separately, while another displays a refund after the button press. Read the exact model manual before deciding that a clock is wrong. Preset numbers are not interchangeable across clock families.

Test with a short practice control and a stopwatch before a club session. Let one move run longer than the allowance, then make a quick move. Compare the result with your written expectation. Stop the practice game and reset deliberately rather than changing settings during a real game.

Tournament setup deserves a second check

FIDE’s current electronic-equipment specification says Fischer increment is added before the first move. That does not mean you should manually add time on top of a preset that already implements it. Check how your particular clock starts the selected control and have the arbiter resolve uncertainty.

Before play, confirm both sides have the intended time, the correct side starts and the sound setting matches the event. Know how to pause without resetting. If an error occurs in competition, stop the clocks and call the arbiter rather than improvising a time correction.

Choose by the required mode

For a purchase, list the actual controls your club uses. Then verify that the clock supports those methods and any necessary stages. A device with many presets is inconvenient if the one you need cannot be programmed clearly.

Are increment and delay interchangeable? No; unused increment can accumulate and unused delay cannot. Is Bronstein another name for Fischer? No. The quickest way to avoid a wrong setup is to write down one short worked example and confirm that the chosen mode behaves as expected before the event.

Sources and further reading