A snapped garage door spring is one of the most common repair calls homeowners make. And one of the most common mistakes that follows is ordering the wrong replacement.
Spring sizing isn’t intuitive. The numbers stamped on a spring don’t tell the full story, and buying the wrong size means your door won’t balance correctly — putting unnecessary strain on the opener, the cables, and the garage door itself. When professional help is the smarter call, Local Garage Doors brings the expertise to get it right the first time, backed by thousands of 5-star ratings across Google, Yelp, Facebook, and Thumbtack for work done with expert care, accuracy, and a focus on lasting durability.
If your spring has already broken and your vehicles are stuck inside, same-day service is one call away — reach us at 
866-337-1631, 
email info@localgaragedoors.com, or schedule your appointment today. If you’re trying to understand springs before that happens, this guide covers exactly what you need to know.
Why Spring Size Matters More Than You Think
Garage door springs are precision-engineered counterbalance components. Their job is to offset the full weight of the door so the opener only needs to supply a small amount of force to move it.
When the spring is the wrong size — even slightly — the door becomes unbalanced. An underweight spring puts excessive load on the opener motor. An overweight spring causes the door to fly up faster than it should and puts stress on cables and drums.
Getting the size right isn’t optional. It’s what determines how long your opener, cables, rollers, and tracks last.
Torsion Springs vs. Extension Springs
Before measuring, you need to know which type of spring system your door uses.
Torsion springs mount horizontally above the garage door opening on a metal shaft. They work by twisting (torquing) as the door moves. Most modern residential doors use torsion springs because they’re more durable, smoother in operation, and safer when they break — a broken torsion spring stays on the shaft rather than flying loose.
Extension springs run along the horizontal tracks on either side of the door. They stretch and contract as the door opens and closes. These are more common on older or lighter doors and are generally considered less safe when they fail, since a broken extension spring can become a projectile if not fitted with a safety cable.
Local Garage Doors handles both systems — repair, replacement, inspection, and counterbalance — across all makes and models of residential and commercial garage doors.
The Five Measurements You Need
Whether you’re buying a replacement torsion spring or calling a technician, knowing these five specifications will get you — or them — to the right part faster.
1. Wire Size (Gauge)
This is the diameter of the wire used to wind the spring. It’s the most critical measurement because it determines how much weight the spring can support.
Wire size is measured in thousandths of an inch. To measure it yourself, count 10 or 20 consecutive coils, measure that length in inches, and divide to get the per-coil wire diameter.
Common wire sizes range from .192 to .283 inches for standard residential doors. Heavier doors require thicker wire.
A small error in wire gauge produces a large error in spring performance — so take this measurement carefully, or let a professional confirm it.
2. Spring Length
Length is measured from the first coil at one end to the last coil at the other, including any coils seated inside the cones at each end. You do not need to unwind the spring to do this.
For a broken torsion spring, slide the two pieces back together with no gap between them before measuring. This gives you the original length.
Most residential torsion springs fall between 20 and 36 inches. Longer springs generally mean more cycles and longer lifespan, so if you’re upgrading, going slightly longer with the correct wire gauge is worth discussing with your technician.
3. Inside Diameter
The inside diameter determines whether the spring fits over the torsion bar correctly. Measure across the interior opening of the spring — not the outside.
The two most common inside diameters for residential torsion springs are 1¾ inches and 2 inches. Commercial doors often use larger diameters. Using the wrong inside diameter means the spring either won’t fit over the shaft or will wobble and wear unevenly.
4. Spring Wind Direction
Torsion springs are wound either left or right. On a two-spring system, you’ll have one of each. They are not interchangeable — installing a left-wound spring where a right-wound spring belongs will cause the door to operate incorrectly and can damage the system.
To identify wind direction, look at the end of the spring. If the coil wraps clockwise away from you, it’s a right-wound spring. If it wraps counterclockwise, it’s left-wound.
On a single-spring setup, the standard is a right-wound spring — but verify before ordering.
5. Type of Ends (Cones)
Torsion springs have two cones — a stationary cone on one end and a winding cone on the other. These need to match your existing hardware. Most residential systems use standard interchangeable cones, but some manufacturers use proprietary hardware.
If your door is from a specific manufacturer — such as Wayne Dalton or CHI, both of which Local Garage Doors works with regularly — confirm the cone compatibility before purchasing a replacement spring.
Reading the Spring Code
Most torsion springs are stamped or color-coded with a size designation. The most common format is a three-digit number like 728, where:
- The first digit(s) represent the wire gauge
- The last two digits represent the length in inches
So a 728 spring has a wire gauge in the 700 series and is 28 inches long. Spring codes run from the 300 series (heavy-duty, thicker wire) to the 900 series (lighter wire for lighter doors). The 700 series is the most common for standard residential doors.
Color coding on the winding cone is also used by some manufacturers to indicate wire gauge at a glance — though the coding varies by brand, so don’t rely on color alone to match a spring.
A Word on Safety
Torsion springs operate under extreme tension — enough to cause serious injury or death if mishandled. This is not an exaggeration.
The winding and unwinding process requires specific winding bars, proper technique, and an understanding of how the tension interacts with the cable drums and shaft. The setscrews on the winding cone should never be loosened while the spring is under tension without the right tools and training.
Extension springs carry similar risks. A spring under load that snaps or slips can become a high-speed projectile. Safety cables threaded through extension springs reduce this risk but don’t eliminate it entirely.
Measuring a spring for identification purposes is something most homeowners can do safely. Replacing or adjusting a spring is a different matter entirely. Local Garage Doors strongly recommends leaving installation and adjustment to trained technicians — not because the job is impossible to learn, but because the consequences of getting it wrong are severe.
What Local Garage Doors Handles for You
Local Garage Doors provides a full range of spring-related services:
Broken spring replacement – Same-day service available, 7 days a week. If your spring is broken, technicians carry a wide range of spring sizes and can complete most replacements in a single visit.
Spring and cable inspection with counterbalance – Part of their maintenance service offering, this checks the condition of your springs before they fail, verifies cable tension, and adjusts the counterbalance so the door operates at its correct weight distribution.
Safety inspection – A full safety inspection of the spring system, cables, drums, and associated hardware — identifying wear before it becomes a breakdown.
All work is performed by licensed professionals using high-quality parts and backed by their best-in-industry warranty. Local Garage Doors is fully licensed in California (CA #1023930) and Nevada (NV #0087802) and has over 30 years of combined experience handling spring systems across all major door brands and types.
The Bottom Line
Getting the right spring comes down to five numbers: wire size, length, inside diameter, wind direction, and cone type. Measure carefully, verify the spring code, and never attempt to wind or unwind a torsion spring without proper tools and training.
If you’re not certain about any part of this process — or your spring has already failed — the fastest and safest path forward is a call to a professional.
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