Scale Conversion Calculator – Convert Measurements to a Scaled Size
Scale a measurement to a larger or smaller measurement, which is useful for architecture, modeling, and other projects. You can also add the real size and scaled size to find the scale factor.
Find the Scaled Size
Find the Scale Factor
How to Scale a Measurement Larger or Smaller
Making a measurement smaller or larger, known as scale conversion, requires a common scale factor, which you can use to multiply or divide all measurements by.
To scale a measurement to a smaller measurement, for instance, when making a blueprint, simply divide the real measurement by the scale factor. The scale factor is commonly expressed as 1:n or 1/n, where n is the factor.
For example, if the scale factor is 1:8 and the real measurement is 32, divide 32 ÷ 8 = 4 to convert.
To convert a measurement to a larger measurement, simply multiply the real measurement by the scale factor. For example, if the scale factor is 1:8 and the measured length is 4, multiply 4 × 8 = 32 to convert.
Reducing the Scale Factor
The methods above to convert a measurement assume the scale factor is in the form of 1:n or 1/n, which means some additional work is needed if the ratio is 2:3, for example. When the scale factor is not in an even 1:n ratio, you’ll need to reduce it to 1:n.
Use our ratio calculator to reduce a ratio. You can also reduce a ratio by dividing both the numerator and the denominator by the numerator.
For example: reduce 2/3 by dividing both numbers by 2, which would be 1/1.5 or 1:1.5.
2 ÷ 2 = 1
3 ÷ 2 = 1.5
scale factor = 1:1.5
Commonly Used Architectural Scales
|Architectural Scale||Scale Factor|
|1/16″ = 1′||1:192|
|3/32″ = 1′||1:128|
|1/8″ = 1′||1:96|
|3/16″ = 1′||1:64|
|1/4″ = 1′||1:48|
|3/8″ = 1′||1:32|
|1/2″ = 1′||1:24|
|3/4″ = 1′||1:16|
|1″ = 1′||1:12|
|1 1/2″ = 1′||1:8|
|3″ = 1′||1:4|
Commonly Used Model Scales
|Scale Factor||Model Type|
|1:4||steam trains, RC planes|
|1:8||steam trains, cars|
|1:12||cars, motorcycles, dollhouses|
|1:16||steam trains, cars, motorcycles, military vehicles, figures|
|1:20||formula one cars|
|1:24||cars, trucks, aircraft, dollhouses|
|1:32||1 gauge trains, cars, aircraft, figures|
|1:43||O-gauge trains, cars, trucks|
|1:48||O-gauge trains, dollhouses, Lego minifig|
|1:64||S-gauge trains, diecast cars, Hotwheels:Matchbox|
|1:72||aircraft, military vehicles, boats, cars|
|1:76||aircraft, military vehicles|
|1:87||HO-gauge trains, military vehicles|
|1:144||ships, rockets, spacecraft|
|1:160||N-gauge trains, wargaming|