Fit Guides
7 sizing systems25+ country calculatorsBands 28-60, cups AA-PZero data stored
Every fitting guide on the site, grouped by the question you are actually asking.
Getting sized
- How to measure
- What cup letters really measure
- Sister sizes explained
- Sizing through life stages
- Pregnancy and postpartum
Checking and fixing fit
- The 10 fit checks
- Fit problems hub
- Band rides up in the back
- Breast tissue spills over the cups
- Cups gape or wrinkle
- Straps dig into shoulders
- Underwire pokes or sits on tissue
- When to replace a bra
Choosing styles
Written by the BraSizeConversion fit team. Last updated August 2026.