SE scale is a designation used by some modellers to describe miniature (model) trains which run on either Gauge 1 (45 mm or 1.772 in) track or O gauge (32 mm or 1.26 in) track. In the SE scale, 7/8 of an inch equals one foot, which is a ratio of 1:13.7. On 45 mm (1.772 in) gauge track this represents real life narrow-gauge railways that are 2 ft (610 mm) gauge, while on 32 mm (1.26 in) gauge track this represents 18 in (457 mm) railways.

Modelling on a scale where 7/8 inch = 1 foot is relatively new (within the last 20 years)[year needed] and, as a result, the majority of the modellers build from scratch.