Scale Converter
Switch between a scale ratio and a real millimetre measurement — enter the real-world size or the model size, and the other is calculated instantly.
Converted measurement
How the conversion works
A scale of 1:N means the model is 1/N the size of the real thing in every dimension. To go from a real-world length to a model length, divide by N. To go from a model length back to real life, multiply by N. The calculator does the arithmetic and converts the result into millimetres, centimetres, inches, metres, and feet so you can work in whichever unit your reference material uses.
This is handy for checking whether a model matches its stated scale, sizing a display base or diorama to a real vehicle's footprint, or comparing two models built at different scales side by side.
Frequently Asked Questions
What does a scale like 1:24 actually mean?
A scale of 1:24 means every 1 unit of length on the model equals 24 of the same unit in real life. A 4,800 mm (4.8 m) car built at 1:24 comes out to 200 mm long as a model — divide the real size by the scale number to get the model size, or multiply the model size by the scale number to get the real size.
Why do cars, planes, trains, and ships use different common scales?
Each hobby settled on scales that suit its subject and display space. Die-cast cars are commonly 1:18, 1:24, 1:43, or 1:64; aircraft are often 1:48 or 1:72; model railroading uses named scales like HO (1:87) and N (1:160); ships range widely, often 1:350 or larger for warships. The calculator covers the common ratios across all of them.
My model's box says a scale but my measurement doesn't match exactly — why?
Manufacturers round real-world dimensions and tooling introduces small variances, so a model rarely matches its stated scale to the millimetre. Treat the calculator's result as the expected size for a precise scale; a few percent of difference against a real model is normal.
Educational tool only. Results are mathematical estimates rounded for display; a real model's exact dimensions can vary slightly from its nominal scale due to manufacturer rounding and tooling tolerances.