In standard Counter-Strike bomb-defusal mode, the planted bomb takes 40 seconds to explode.
Terrorists win the round if the bomb detonates after being planted at one of the two bombsites. Counter-terrorists can prevent that outcome by eliminating the attackers before the plant, or by defusing the bomb after it has been planted.
The 40-second timer creates a distinct tactical phase. Terrorists can use the remaining time to defend the site, while counter-terrorists must decide whether to retake immediately or preserve enough time for a defuse. The bomb’s beeping becomes faster as detonation approaches, providing an audio warning.
A successful defuse ends the round before the explosion. In standard rules, a counter-terrorist with a defuse kit takes less time to defuse than one without a kit, making kits especially valuable during retakes.