Free Garage Door Spring Calculators

Find the right torsion springs for your garage door. Size new springs from your door's weight, check the springs you have, or work out what your door weighs. Free, no sign-up, in inches or millimetres.

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Spring size calculator by door weight

Enter your door's weight and height. Get torsion springs that balance it: wire size, length and inside diameter, with cycle life options from 10,000 to 50,000.

Garage door spring calculator

Have a spring in front of you? Enter its wire size, inside diameter and length to see how much it lifts, how many turns it needs and how long it should last.

Garage door weight calculator

Estimate how much your door weighs from its size, material and model, then carry the weight straight into the spring size calculator.

How to know what springs to buy

There are two ways to find the right garage door springs, and both take a few minutes:

  1. Measure your old springs: wire size, inside diameter and length of the coils, plus which way they are wound. Check them in the spring calculator.
  2. Start from the door's weight when the old springs are broken, missing or were never right. Use the spring size calculator by door weight.

The full buying guide walks through each step, what to write on the order, and how to stay safe.

Measuring guides

Garage door torsion springs are under high tension. The calculators tell you what to buy; winding and installing springs safely takes proper winding bars and training. If in doubt, call a garage door technician.

Frequently Asked Questions

Is SpringCalc really free?

Yes. Every calculator is free to use, with no sign-up and no email address. It works on phones, tablets and computers, in feet and pounds or in millimetres and kilograms.

What does a garage door spring calculator do?

It works out which torsion springs will balance your door. From the door's weight and height it lists spring sizes that lift it: wire size, inside diameter and length. From the size of a spring you already have, it tells you how much weight that spring lifts, how many turns it needs and how many open-and-close cycles it should last.

How do I know what springs to buy for my garage door?

Measure your old springs (wire size, inside diameter, length of the coils and wind direction) and check them in the spring calculator, or start from your door's weight with the spring size calculator by door weight. The buying guide explains both.

Does SpringCalc work for extension springs?

No. SpringCalc is built for torsion springs, the springs mounted on a bar above the door. Extension springs run along the horizontal tracks on each side and are sized differently.

How accurate are the results?

The calculators use standard torsion spring engineering formulas, checked against published spring charts. Use the results to choose and order springs, and confirm the sizes with your supplier before installing.