Reference Guide: Model Train Scale
A common set of questions among model railroaders relates to model train scale. What are the most popular scales and how do those different scales compare? Which scale should I choose?
There are many different popular model train scales and it can get confusing as to which scale is best. In fact some hobbyists choose to mix scales on their layout. Scale or proportion refers to the ratio of model size to actual size.
Here’s a quick model train scale reference to help understand the most popular scales. I’ve added information to help visualize the proportion of each scale, showing the approximate actual size for 1 inch of the model size. The sizes are ordered from largest models to smallest models.
Model Train Scale Reference
| Common Name |
Scale | Gauge | Model Size |
Approximate Actual Size |
| G Scale or LGB Scale |
1:22.5 | 1.75″ | 1 inch | 1 foot, 11 inches |
| O Scale | 1:48 | 1.25″ | 1 inch | 4 feet |
| O27 Scale | 1:48 | 1.25″ | 1 inch | 4 feet |
| S Scale | 1:64 | 0.875″ | 1 inch | 5 feet, 4 inches |
| HO Scale | 1:87 | 0.650″ | 1 inch | 7 feet, 4 inches |
| TT Scale | 1:120 | 0.47″ | 1 inch | 10 feet |
| N Scale | 1:160 | 0.353″ | 1 inch | 13 feet, 4 inches |
| Z Scale | 1:220 | 0.257″ | 1 inch | 18 feet, 4 inches |
Scale: Ratio of the scale to actual size. For example, the popular HO Scale model is 1:87 or 1/87th of actual size.
Gauge: The space between the rails of railroad track. The larger the gauge, the larger the scale model and the more space required in a layout.
Sizes: The sizes help visualize the scale. For example, 1 inch in the popular HO scale is approximately 7 feet, 4 inches in actual or full size.
G Scale: G scale model trains or LGB model trains are the largest popular scale of model trains. This large-scale model railroad is sometimes referred to as garden scale train. They rarely derail and are relatively easy to operate. However, G Scale requires a large space for layout and equipment can get expensive.
O Scale: The O Scale model train is a large-scale model often preferred for the model’s size and authenticity. As with G Scale, this scale is easier to operate. However, O Scale equipment can be pricey.
O27 or O30 Scale: O27 Scale models are similar to O Scale model trains, but can support a tighter curve radius. O27 track will make a 27” circle as compared to O scale track which make a 31” circle. This scale tends to be a niche scale and equipment can be hard to find.
S Scale: S Scale is a fast growing size as it requires only ten percent more space than HO scale.
HO Scale: HO Scale is the most popular model train scale. Not only does the HO model train layout fits well on a standard 4’ x 8’ sheet of plywood, but the equipment is easy to find and competitively priced. HO Scale lends itself well to realistic layouts.
TT Scale: TT Scale has a limited following in the United States but is popular in Europe
N Scale: While small in size, N Scale allows for a very large layout in a limited space. This is a great choice when the layout and scenery is a priority. However, the small size of the equipment can be a challenge to work with. As it’s not as popular as HO Scale, there aren’t as many equipment options.
Z Scale: This scale is a great option when available space is a premium. It allows for a large layout in a small space.
Which model train scale is best for you? It depends on your situation. I hope this overview of model train scale helps get you understand the different scales and narrow the options as to which scale is best for you.
