Garage Door Torsion Spring Calculator
Find the lifting capacity, turns and life cycles of a garage door torsion spring from its wire size, inner diameter and length.
Find the lifting capacity, turns and life cycles of a garage door torsion spring from its wire size, inner diameter and length.
Measure the length of 10 coils with a tape measure and divide by 10. For example, if 10 coils measure 2.25 inches, the wire size is 0.225. Our wire size guide shows the process step by step.
The standard 4 inch residential cable drum. If your door uses a 5.25 inch drum, common on taller doors, select it in the Drum dropdown and the results adjust automatically.
One cycle is one full open and close of the door. The number is an engineering estimate of the spring's fatigue life at the calculated stress. Rust, missing lubrication and poor balance shorten it.
Most doors use a pair of springs that share the load. If your door has two springs, together they lift twice the shown capacity, so each spring should be sized for half the door weight.
Use our door weight calculator to estimate it from the size and material, then use the Springs By Door tool to get matched spring options.