Scale calculator
Build a dinosaur model, read a map, or resize a drawing. Convert between real and model lengths with a shared 1:N scale.
Model length at 1:10012 cm
Formula: model length = real length ÷ N. Convert both measurements to the same unit before applying the ratio.
How to use this tool
At 1:100, one model unit represents 100 of the same real-world units. Length scales linearly; area and volume scale by the square and cube. A map’s local scale can vary with projection.
An example to try
A 12 m animal at 1:100 becomes a 12 cm model.
NIST · Length and unit definitions ↗
Is it free?
Yes. No account or payment is required. Calculations run in your browser. If JavaScript is unavailable, the explanation and source links remain readable, but the interactive controls require it.