Pick one car or two, and measure the garage: the front wall inside, the ceiling and the depth. You get the door size to order, its rough opening, and whether there is room for its tracks and springs.
Garage door size
An 18 × 7 ft garage doorrough opening 18′ × 7′ · 1′ of wall each side · 2′ of headroom
Quick answer: a single garage door is 8 or 9 ft wide by 7 ft tall; a double, for two cars, 16 ft wide (up to 18) by 7 ft (Clopay). Go 8 ft tall for SUVs and pickups. The garage needs 3¾″ of wall each side, 12″ above the opening for torsion springs, and the door’s height plus 18″ of depth for the tracks.
How to use the garage door size calculator
- Pick one car or two through the door, and cars or taller SUVs, pickups and vans.
- Measure the front wall inside, side wall to side wall.
- Measure the ceiling to the lowest thing above the door’s path (a beam, a pipe, the opener), and the depth to the back wall.
- Read the door to order, its rough opening and the room its tracks need. Copy link keeps the result.
The rules behind the numbers
Sizes: Clopay’s standards
Door maker Clopay: a single door 8 × 7 ft (“standard for single-car garages”) or 9 × 7 (“increasingly popular … for extra clearance”); a double 16 × 7 (“the classic standard for two-car garages”), up to 18 ft wide; 8 ft tall “for larger SUVs, trucks”. The calculator takes the widest door that fits your wall with its side room: a wider opening is easier to drive through.
The room the tracks need
Clopay asks for 3¾″ of wall each side of the opening, 12″ above it for torsion springs (10″ for extension springs), and the door’s height plus 18″ of ceiling behind it for the tracks. With less headroom, a low-headroom track gets by on 9″ (front mount) or 4½″ (rear mount).
The rough opening
The framed opening, without the stop molding, should match the door’s size (Clopay): a 16 × 7 ft door goes in a 16 × 7 ft opening.
Standard garage door sizes and the room they need
| Door | For | Front wall at least | Ceiling at least | Depth for the tracks |
|---|---|---|---|---|
| 8 × 7 ft | one car | 8′ 7½″ | 8′ | 8′ 6″ |
| 9 × 7 ft | one car | 9′ 7½″ | 8′ | 8′ 6″ |
| 9 × 8 ft | one SUV or pickup | 9′ 7½″ | 9′ | 9′ 6″ |
| 16 × 7 ft | two cars | 16′ 7½″ | 8′ | 8′ 6″ |
| 18 × 7 ft | two cars | 18′ 7½″ | 8′ | 8′ 6″ |
| 16 × 8 ft | two SUVs or pickups | 16′ 7½″ | 9′ | 9′ 6″ |
With torsion springs (12″ above the opening). Extension springs need 2″ less ceiling; a low-headroom track, less again.
Three worked examples
A 20 × 22 ft two-car garage, 9 ft ceiling. An 18 × 7 ft door: 1′ of wall each side and 2′ of headroom, room for torsion springs.
A narrower garage, 16′ 8″ wide inside, 8 ft ceiling. An 18 ft door would need 18′ 7½″, so a 16 × 7 ft door, with 4″ each side and exactly 1′ of headroom.
One pickup, an 8′ 8″ ceiling. A 9 × 8 ft door leaves only 8″ above the opening: order it with a rear-mount low-headroom track.
Common garage door sizing mistakes
- Measuring the ceiling, not the lowest thing under it. A beam, a pipe or the opener’s rail decides the headroom.
- Forgetting the side room. A 16 ft door in a 16 ft wall leaves nowhere for the tracks.
- A 7 ft door for a tall truck. Check the height with the roof rack; 8 ft doors are made for it.
- Ordering by the old door, not the opening. Measure the framed opening without the stop molding.
Sizing the house’s own doors too? The free door size finder gives interior, front and patio doors with their rough openings; the exterior house color visualizer tries a new color on the garage door, and the free 2D room planner draws the garage to scale.
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Garage door size questions
What are the standard garage door sizes?
Single doors 8 × 7 and 9 × 7 ft; double doors 16 × 7 ft, up to 18 ft wide; 8 ft tall for SUVs and trucks (Clopay). Doors 9–10 ft tall and more are made for campers and RVs.
What size is a single car garage door?
8 × 7 ft, the standard, or 9 × 7 ft for more room either side of the car. It needs 3¾″ of wall each side: 8′ 7½″ or 9′ 7½″ of front wall.
What size is a 2 car garage door?
16 × 7 ft, the classic, or 18 × 7 ft, which needs a front wall of at least 18′ 7½″ inside. 8 ft tall for SUVs and pickups.
How tall is a standard garage door?
7 ft. 8 ft doors are widely sold for larger SUVs and trucks (Clopay).
How much headroom does a garage door need?
12″ above the opening for torsion springs, 10″ for extension springs (Clopay). A low-headroom track needs 9″ front-mounted, 4½″ rear-mounted.
What is the rough opening for a garage door?
The door’s own size: the framed opening, without the stop molding, should match it (Clopay). A 9 × 7 ft door goes in a 9 × 7 ft opening.