A timing window, in general, is the maximum allowed time leniance of a particular action. For example, when strumming, the software generally checks to see if the closest note that hasn't already been hit is within a certain threshold, or timing window. If it is, the game registers a hit; if not, then it's a miss.

The image to the right shows an example timing window for Game_RockBand2 Rock Band 2∞ in red, though it is not precise.

Enabling the Precision Mode cheat in Game_GuitarHeroIIILegendsOfRock Guitar Hero III∞ and Game_GuitarHeroAerosmith Guitar Hero: Aerosmith makes the timing window for notes smaller, while Easy Expert (Game_GuitarHeroIIILegendsOfRock GH3∞ only) makes the timing window larger.

The following actions have timing windows:

• Hammer-ons Hammer-ons and Pull-offs∞
• Strumming (to hit a note)