How big is a 32D bust?

Example: If your underbust = 73 cm, your band size is 34. If your overbust = 85 cm, in the 34 band size chart, your bra size is 34B. The measuring tape should be somewhat loose and measured at the fullest part of your chest. U.S.
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Step 2: Overbust (cup size)
32 – Band Size
Your bra size: 32C 32D

Is 32D small or medium?

With standard sizing, you can expect a 32C and a 32D to be bracketed together as a Small, a 34C and a 34D to both be Medium, a 36C and 36D to equate a Large, and so on, up through the fit range.