A faster way to convert scales
Whether you build model aircraft, paint miniatures, lay out a model railroad or draw architectural plans, this tool turns real-world measurements into scaled sizes — and back again — without any maths. Choose your scale from the preset list instead of memorising ratios, mix metric and imperial units, and read the result the moment you type.
Common scales reference
How big a 10 m (1000 cm) real object becomes at popular scales:
| Scale | Common use | 10 m real → model |
|---|---|---|
| 1:18 | Diecast cars, large models | 55.6 cm |
| 1:35 | Military models, tanks | 28.6 cm |
| 1:48 (O) | Aircraft, O-scale trains | 20.8 cm |
| 1:72 | Aircraft, vehicles | 13.9 cm |
| 1:87 (HO) | Model railroad (HO) | 11.5 cm |
| 1:100 | Architecture | 10.0 cm |
| 1:160 (N) | Model railroad (N) | 6.3 cm |
| 1:220 (Z) | Model railroad (Z) | 4.5 cm |
Frequently asked questions
How do I convert a real size to a model scale?
Set the “From” scale to Real life (1:1), enter the real-world measurement, then set the “To” scale to your model scale (for example 1:72). The model size appears instantly.
What is a scale factor?
A scale factor is the ratio between a model and the real object. At 1:48, the scale factor is 1/48 — every part of the model is 48 times smaller than the real thing.
Can I convert between two different scales?
Yes. Set the “From” scale to the original scale and the “To” scale to the target scale — for example from 1:48 to 1:72 — and the calculator keeps the real object the same size while resizing the model.
Which units are supported?
Millimeters, centimeters, meters, inches and feet. You can mix units freely — for example enter meters and read the result in centimeters.