Scale — Model railway
HO scale
HO scale
1:87
At 1:87 a person is 20.1 mm tall and a 19 m locomotive is 21.8 cm long. Everything below is drawn at 1:87, by an atelier that builds architectural models at the scales either side of it.
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Scale1:87
Subjectlocomotive, person, signal
Grid1 cm on the model
DrawnAtelier AMOD
Sheet17 / 20
Person20.1 mm1.75 m
Track gauge16.5 mmbetween the rails
Carriage27.6 cm24 m long
Locomotive46 mm4 m tall
01Converter
Real size,
Real size,
1:87 size
For a whole building at every scale at once, use the scale calculator.
| Standard track gauge 1.44 m | 16.5 mm |
|---|---|
| A person 1.75 m | 20.1 mm |
| A locomotive, height 4 m | 46 mm |
| A signal 6 m | 69 mm |
| A locomotive, length 19 m | 21.8 cm |
| A carriage 24 m | 27.6 cm |
| 1 mm on the model | 8.7 cm |
|---|---|
| 1 cm on the model | 87 cm |
| 5 cm on the model | 4.35 m |
| 10 cm on the model | 8.7 m |
| 30 cm on the model | 26.1 m |
| 50 cm on the model | 43.5 m |
| 1 m on the model | 87 m |
02The world's railway scale
At 1:87
I
Track gauge
16.5 mm: standard gauge of 1,435 mm at 1:87. HO stands for half O, half the size of O scale.
II
Where it is used
The most widely used model railway scale in the world.
III
For architecture
HO figures are 15% larger than 1:100 figures: a 1.75 m person is 20.1 mm against 17.5 mm. Beside a 1:100 building they read as tall people.
03One figure, every scale
The same person
The same person
at every scale
Architecture
Model railway
04From the archive
Built near 1:87
The archive's models at 1:75 and 1:100, the architectural scales closest to 1:87.
05The scale rule
Every scale
Architecture ↑Model railway ↓
06Questions
On 1:87
What is the ratio of HO scale?
HO scale is 1:87. One millimetre on the model is 8.7 cm in reality and one centimetre is 87 cm. 16.5 mm: standard gauge of 1,435 mm at 1:87. HO stands for half O, half the size of O scale.
How tall is a person in HO scale?
A person 1.75 m tall is 20.1 mm in HO scale, and a child of 1.2 m is 13.8 mm. A 4 m locomotive stands 46 mm above the rails.
How long is a train in HO scale?
A 24 m passenger carriage is 27.6 cm and a 19 m locomotive 21.8 cm. A twelve-carriage train of 300 m would be 344.8 cm.
Can HO scale figures be used in an architectural model?
HO figures are 15% larger than 1:100 figures: a 1.75 m person is 20.1 mm against 17.5 mm. Beside a 1:100 building they read as tall people.
Your building, at 1:87, built by hand.