How to convert real dimensions to model scale
Divide the real-world measurement by the scale denominator, then convert the result into the workshop unit you prefer.
How it works
At 1:48 scale, every 48 real units become 1 model unit.
Checked example
Example: 6 feet is 72 inches. At 1:48, 72 ÷ 48 = 1.5 inches, or 38.1 mm.
Workshop notes
Keep units consistent and round only the final workshop measurement.
Start with one consistent unit
Write every real measurement in the same unit before dividing. Six feet can become 72 inches or 1,828.8 millimetres; both paths give the same answer when handled consistently. Mixing feet with millimetres inside one calculation is a common source of large errors.
Convert a complete opening
For a real door measuring 84 × 36 inches at 1:48, divide both dimensions by 48. The model opening is 1.75 × 0.75 inches, or 44.45 × 19.05 mm. Add the frame and clearance as separate fabrication allowances rather than changing the scale formula.
Preserve exact and practical values
The mathematically exact result may fall between ruler marks. Keep the exact millimetre or decimal-inch value for design files, then use the displayed fraction and rounding difference for hand cutting. Round once, at the final workshop step.
Build one checked worksheet
Enter walls, doors, windows, furniture, and trim as separate items. A single worksheet makes it easier to catch a dimension entered in the wrong unit and prevents small rounding choices from drifting across the project.
Frequently asked questions
Do I divide or multiply for real size to model size?
Divide the real-world dimension by the scale denominator. At 1:48, divide by 48.
Can I enter feet and receive millimetres?
Yes. The converter normalizes the input and displays both millimetres and inches.
Why is my ruler fraction slightly different?
The fraction is rounded to a mark your selected ruler can show. The exact value and rounding difference remain visible.
Should material thickness be scaled exactly?
Start with the exact scaled design, then adjust for available sheet thickness, strength, kerf, or printing limits.