Skip to content
Calculator Tools
Map & Scale Calculators

Model Scale Calculator

Scale model dimensions from the real thing, for railways, dioramas and scale kits.

Enter values

Results update as you type.

Result

Scaled length

51.724 mm

Scaled width
20.69 mm
Scaled height
16.092 mm
Scale
1 : 87
Volume ratio
0.000001519
a model holds far less than you expect
A 1.8 m person at this scale
20.69 mm

About the Model Scale Calculator

Scale model dimensions from the real thing, for railways, dioramas and scale kits.

Also known as: scale model calculator, model railway scale, diecast scale converter, miniature scale.

How to use this calculator

  1. Enter scale, convert, length, width and the other fields.
  2. The result updates instantly as you type — press Calculate (or Enter) at any time.
  3. Review the breakdown shown under the main result.
  4. Use Copy result or Share to save the answer or send a link with your inputs.

Formula

model size = real size ÷ scale denominator

Worked example

Using the values pre-filled in the calculator above:

  • Scale: HO gauge (1:87)
  • Convert: Real → model
  • Length = 4.5
  • Width = 1.8
  • Height = 1.4
  • Units: Metres (real) / mm (model)

the calculator returns:

  • Scaled length: 51.724 mm
  • Scaled width: 20.69 mm
  • Scaled height: 16.092 mm
  • Scale: 1 : 87