When would I convert between scales?

When adapting plans or references from one scale to another. For example, using a 1:72 kit as a reference to scratch-build the same subject in 1:48, or checking if a diorama accessory from one scale works in another.

How does the maths work?

The calculator first converts the source-scale measurement back to real-world size (multiply by the source scale factor), then converts to the target scale (divide by the target scale factor). The net effect is multiplying by the ratio of the two scale factors.

Can I use this to resize 3D print files?

Yes. Find the conversion factor (source scale / target scale) and use it as the scaling percentage in your 3D slicing software. For example, 1:72 to 1:48 = 72/48 = 1.5, so scale the file to 150%.

ModelCalcs

Mixed Scale Calculator — Convert Between Scales

Convert a dimension directly from one model scale to another without needing to know the real-world size.

Source Measurement

Measurement on the source-scale model

From Scale

To Scale

How We Calculate This

The calculator converts from one scale to another via the real-world dimension.

Formula

Target size = Source size × (Source scale ÷ Target scale)

Example: A 1:72 model part measures 15mm. To make the same part in 1:48:
15 × (72 ÷ 48) = 15 × 1.5 = 22.5mm.

Frequently Asked Questions

Related Calculators

Scale Calculator

Convert any measurement between real world and model scale. Supports all common scales.

Real to Scale Converter

Convert a real-world measurement down to your chosen model scale.

Scale to Real Converter

Convert a model measurement back up to find the real-world equivalent.

Scale Ratio Calculator

Find the scale ratio from a real measurement and its model equivalent.

Scale Speed Calculator

Calculate the correct scale speed so your model moves at a realistic pace.

Last updated: February 2026

All calculations are estimates. Always verify quantities before purchasing materials.