Torsion spring winding calculator
How many turns to wind a torsion spring? For a standard-lift residential door on 4-inch drums it comes down to door height. Get the full turns and quarter-turns, then always wind to the door or spring maker's spec.
Turn counts here are for standard lift on 4" (400-series) drums. High-lift and low-headroom use specialty drums with their own charts.
The standard-lift rule
For a standard-lift residential door on ordinary 4-inch (400-series) drums, the cable travel equals the door height, so the winding turns track door height almost exactly: turns ≈ door height in feet + about 3/4 of a turn. A 7-foot door lands at 7.75 turns (31 quarter-turns), an 8-foot door at 8.75.
| Door height | Full turns | Quarter-turns |
|---|---|---|
7 ft | 7.75 | 31 |
7.5 ft | 8.25 | 33 |
8 ft | 8.75 | 35 |
9 ft | 9.75 | 39 |
10 ft | 10.75 | 43 |
12 ft | 12.75 | 51 |
14 ft | 14.75 | 59 |
Winding safely
- Use two winding bars that fully seat in the cone holes, never a screwdriver or rebar.
- Wind up (the direction that raises the door), keeping your body out of the bar's arc.
- Add the small drum-specified stretch after reaching the turn count.
- Set the cone screws on clean shaft, then test: the door should hold at waist height and float through travel.
Not sure of the spring itself? Start with the spring size calculator to confirm the wire, ID, and wind before you rebuild.
Want the full walkthrough, not just the tool? Read the field guide: How many turns on a garage door spring? The rule, and the exceptions
Frequently asked questions
How many turns do you wind a 7-foot garage door spring?
On a standard-lift door with 4-inch drums, about 7.75 full turns (31 quarter-turns). The rule of thumb is door height in feet plus roughly 3/4 of a turn, so an 8-foot door is about 8.75 turns. Always confirm against the door or spring manufacturer's turn spec.
Which direction do you wind the spring?
You wind UP (raising the door direction) with winding bars; never wind down under load. On a standard center setup the left spring and right spring wind opposite directions per their cones. Follow the spring's wind (red cone = left-wound, black = right-wound).
How do I count quarter-turns?
With winding bars, each time you insert a bar and rotate to the next hole is a quarter turn (four holes = one full turn). Count out loud; a 7-foot door is 31 quarter-turns.
Is winding a spring safe to DIY?
No. A wound torsion spring stores enough energy to break bones or kill. Use proper winding bars that fully seat in the cone, keep your body out of the arc, and if you are not trained, hire a technician.
Audrey does this in the truck, hands-free.
This calculator runs the exact logic built into Ask Audrey, where your techs just ask out loud and get the answer cited to your own manuals (and identify the spring first). Every tech, a senior tech.