What are the model railway scales and gauges?

So you have decided to build a model railway now you ask “What are the model railway scales and gauges?”

Scales and gauges often pop up as a question, the most common gauge is OO, followed by N gauge and now O gauge, there are others out there going from gauge 1 in the garden right down to Z gauge.

As a basic rule:

  • OO gauge is 4mm to the foot or 1-76 scale,
  • O gauge is 7mm to the foot or 1-43 scale and
  • N gauge is 2mm to the foot or 1-148 scale.

Additionally to this you  can also have the Narrow gauge versions, for example; the narrow gauge for OO is 009 everything is the same scale but it is a representation of the narrow gauge railways such as those found in North Wales and industrial areas.

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About North Western Models


At North Western Models we believe that it’s the detail that brings a model railway to life.

North Western Models was established in 2015 by Kevin Colley and Christopher Gore as an online model shop based in Stockport, Cheshire. Initially dealing with high quality detailing accessories and kits, North Western Models prides itself in serving the model railway community to promote the notion that detailing helps to bring a model railway to life.

Kevin and Christopher have a lifelong passion with railways in general and also with model railways. Between them, they have planned, built and exhibited a number of layouts in 00 and N gauge at various local model shows. Kevin and Christopher regularly attend a number of exhibitions each year, either trading as North Western Models or with one of their layouts which is currently on the exhibition circuit.

Kevin Colley, North Western Models Co-founder
Kevin Colley, North Western Models Co-founder