In OSRS, the number of spells you can cast per minute depends on the type of spell and your equipment.
For regular combat spells, you can cast 20 spells per minute. This works out to 1,200 spells per hour. Each combat spell takes 5 game ticks to cast, with each tick being 0.6 seconds.
If you use long-range combat spells, the casting speed drops to 4 ticks, letting you cast fewer spells per minute.
Before you start intense magic training, you might want to buy OSRS gold to get the right equipment for maximum efficiency.
The harmonized nightmare staff is a special weapon that changes these numbers. It lets you autocast at 4 ticks instead of 5, making your spell casting faster than normal.
These speeds stay the same no matter what combat spell you use. Whether it's a basic fire strike or a powerful ice barrage, the tick system remains constant.