Sometimes, people can get confused about the various sizes of models and the differences between scales and gauges in the model community. Hopefully, this guide will clarify these concepts.

“scale” and “gauge” are frequently used interchangeably, but they represent different aspects of the model.

Gauge: Gauge refers to the distance between the rails on the track, typically measured in millimeters or inches. It determines the track’s width and affects the compatibility of trains and track components.

Scale: Scale refers to the size ratio between the model and the real-life object it represents, usually expressed as a ratio. For instance, in OO scale, 1 unit on the model corresponds to 76 units in real life. Scale influences the size of trains and other elements, such as buildings and scenery.

In summary:

Scale: defines the size of the model in relation to the real thing.

Gauge: defines the distance between the rails on the track.

While both are related, they are distinct, and each plays an important role when designing a model railway layout or diorama.

We have made a simple diagram of the differences above.