Size Calculator
Find Your THEOS Size
Enter both measurements in inches for the most accurate fit.
How To Measure
Find your perfect fit in 2 simple steps.
Step 1 - Underbust
Wrap the tape snugly around your ribcage, directly beneath your bust.
Step 2 - Overbust
Wrap the tape around the fullest part of your bust, keeping it level.
Frequently asked questions
How accurate is the THEOS Size Calculator?
Our calculator uses your underbust and overbust measurements to recommend the closest THEOS size. For the best results, measure yourself using our guide before entering your measurements.
How should my bra fit?
A well-fitting bra should feel supportive and comfortable without digging into your skin, slipping off your shoulders, or leaving gaps in the cups.
Can I exchange my size if it doesn't fit?
Yes, If your size isn't quite right, please contact us and we'll guide you through the exchange process according to our exchange policy.
Why does my THEOS size differ from other brands?
Sizing can vary between brands. That's why we've created a dedicated THEOS Size Guide and Calculator to help you find your best fit within our collection.
What measurements do I need?
You'll only need two measurements:
Underbust - around your ribcage, directly beneath your bust.
Overbust - around the fullest part of your bust.
We're here to help
Not sure about your size?
Send us your measurements and a real person will help you find your perfect THEOS fit.