Shoe Size Converter Calculator Formula
Understand the math behind the shoe size converter calculator. Each variable explained with a worked example.
Formulas Used
US Men's Size
us_mens = (foot_length_cm - 22) * 3 / 2.54 + 3UK Size
uk_size = (foot_length_cm - 22) * 3 / 2.54 + 2.5EU Size
eu_size = foot_length_cm * 1.5 + 2Variables
| Variable | Description | Default |
|---|---|---|
foot_length_cm | Foot Length(cm) | 27 |
How It Works
How Shoe Size Systems Work
Each sizing system has a different scale based on foot length. This calculator converts using approximate formulas.
Approximate Formulas
EU = Foot Length (cm) x 1.5 + 2
US Men's and UK are based on barleycorn increments (1/3 inch) from reference points.
Always try shoes on, as sizing varies by manufacturer.
Worked Example
Foot length of 27 cm.
foot_length_cm = 27
- 01US Men's = (27 - 22) x 3 / 2.54 + 3 = 8.9
- 02UK = (27 - 22) x 3 / 2.54 + 2.5 = 8.4
- 03EU = 27 x 1.5 + 2 = 42.5, rounded to 43
Ready to run the numbers?
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