Tools

Garage door size & fit checker

Measure your opening and compare it with sourced manufacturer dimensions, with clear limits on what a tool can confirm.

Enable JavaScript to use the interactive tool. The explanations and checklist below work without it.

Measure before you compare

Record the opening width at the top, middle and bottom, and height on both sides. Record the smallest dimension and note any uneven surfaces. Measure clear space above and on either side of the opening, plus unobstructed garage depth. Do not dismantle the door or its mechanism to measure it.

Diagram showing opening width, height, headroom and side room; depth is measured inside the garage.

What the checker can tell you

It compares available clearances with the manufacturer-specific examples in our data. It cannot match a structural opening straight to a nominal ordering size. The roller and side-hinged information is incomplete, so those options need a model-specific specification rather than a guessed allowance.

For the documented manual Garador sectional example, minimum depth is door height plus 510 mm. This is not a general formula for all sectional doors. Operator rails and track arrangements change the requirements.

A worked clearance example

If the surveyed door height were 2,100 mm, the documented manual sectional example would need 2,610 mm depth (2,100 + 510). With 2,700 mm available, this provisional depth check has 90 mm to spare; opening height is only a stand-in until a survey establishes the actual door height. The engine records no clearance shortfall in the supplied example. This checks one clearance only: ordering size and complete fit remain unconfirmed.

See our measuring guide and the door-type guide before booking a survey.

Sources & further reading

Checked 2026-10-25. Specifications and rules can change; confirm before ordering or starting work.