What this calculator does
Brand fit varies because shoes are built on different lasts. This calculator turns a usual size into a first-try size for a selected brand, with a practical fit note.
Formula used
The calculator converts the usual size to an approximate UK baseline, applies a small brand fit adjustment, then converts back to common systems.
How to read the result
Use this as a starting point only. Model, width, material and personal fit preference can matter more than the brand average.
Assumptions
- Adult sizing only.
- Uses broad fit tendencies, not an official brand chart.
- Half sizes are approximate.
Sources and checks
This calculator uses a standard public formula. Where rules or thresholds can change, source links are listed on the relevant page.
Frequently asked questions
Why not give one definitive brand size?
A brand can have several lasts and product lines. A running shoe, boot and canvas trainer may all fit differently.