O Scale Calculator

O scale is the classic large model railroad scale, commonly 1:48 in the United States. Its size gives a substantial, detailed feel — at 1:48, a 48 cm real measurement becomes 1 cm on the model.

Scale Converter

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What fits at 1:48 (1:48 (US))

Larger model railroads, toy trains, trackside structures and detailed rolling stock.

Real subject	Real size	1:48 model
40 ft boxcar	12.2 m	25.4 cm
EMD F7 locomotive	15.4 m	32.1 cm
Two-storey house (height)	8 m	16.7 cm
Person	1.8 m	3.8 cm

Frequently asked questions

What ratio is O scale?

In the US, O scale is 1:48. Some European O-scale systems use 1:43.5 or 1:45.

Related scales

→ See all scales