🌸 Bra Fit Education • Sister Size Guide

Sister Size Calculator

Enter your current bra band and cup size to find nearby sister sizes that may offer a similar cup volume with a different band measurement.

Enter Your Current Bra Size

Enter the band number from your current bra size. Common band sizes are even numbers such as 28, 30, 32, 34, 36 and 38.

Enter an even band size between 28 and 60.
Current Cup Size

Select the cup letter from your current bra size.

How sister sizing works: Moving up one band size usually means moving down one cup letter. Moving down one band size usually means moving up one cup letter. This helps keep cup volume approximately similar, although fit can vary by brand and bra style.

Your Sister Sizes

These nearby sizes are calculated from your selected band and cup combination.

Closest sister size with a larger band

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Sister sizes are a starting point. Actual fit can vary between brands, styles and breast shapes.

Larger Band

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One band size larger with one cup letter smaller.

Smaller Band

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One band size smaller with one cup letter larger.

🔒 Need Private Size Guidance?

If you’re unsure which sister size may work better, or you would prefer private help with your bra fit, you can contact Clinical Care directly on WhatsApp.

💬 Chat Privately on WhatsApp →

Related Bra Size Tools

Bra Size Calculator → Bra Size Converter →