Scale conversion for drawings, maquettes, and layout design: pick a standard ratio, enter metric or imperial source lengths, and rely on the same arithmetic rule every time.

Instant Scale Measurement Calculator for Models & Architecture

Enter a full-size span, choose HO, architectural, or diecast ratios, then copy scaled millimetres and companion units for elevations, track plans, and model components.

Source measurement

Decimal in the unit you selected, or feet and inches (for example 6'2" or 6 ft 2 in). When you use feet and inches, that value is used even if another unit is selected.

Scaled result

20.000 mm / 2.000 cm / 0.020 m / 0.787 in / 0.066 ft
Reference and scaled length

Scaled length at 1:50 in millimetres, centimetres, metres, inches, and decimal feet. In the workbench below, the high-contrast bar is your scaled length; lighter shapes are reference-only silhouettes.

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