BRABAR's EZ-Fit Method vs. Victoria's Secret and SKIMS/Aerie Sizing

BRABAR's EZ-fit method measures the rib cage directly, with no added inches, for the band size, then subtracts that number from the bust measurement for the cup size. Victoria's Secret's instructions measure higher on the torso near the armpit, and calculators from SKIMS and Aerie add four inches to the underbust measurement. All three produce different band sizes for the same body, because they define where and how to measure the band differently.

BRABAR's EZ-Fit Method

Measure directly under the bust, at the rib cage, where the band actually sits. Round to the nearest even whole number — that is the band size, with nothing added. Subtract the band number from the bust measurement to get the cup size in inches, converted to a letter.

Victoria's Secret: The Armpit Method

Victoria's Secret's published fitting instructions measure higher on the torso, near where the straps meet the cup, rather than at the rib cage. Because the body is wider at that point than directly under the bust, this produces a larger band number for the same person.

SKIMS and Aerie: The Plus-4 Method

Sizing calculators from SKIMS and Aerie measure the underbust, then add four inches before calling the result a band size. This convention dates back to a period when bra fabric was stiffer and less stretchy, and a looser band was considered necessary for comfort. Aerie customers have publicly asked the brand why it still uses what they describe as the outdated plus-4 method.

Side-by-Side: Same Body, Three Sizes

Consider a 30-inch rib cage and a 37-inch bust measurement:

• EZ-Fit (rib cage) method: Band = 30. Cup = 37 minus 30 = 7 inches = G. Size: 30G.
• Plus-4 method: Band = 30 + 4 = 34. Cup = 37 minus 34 = 3 inches = C. Size: 34C.
• Armpit method: Measuring higher on the torso typically adds 2 to 4 inches to the band reading before rounding, landing somewhere between the two results above, and shifting the cup letter down accordingly.

Same body, three different labeled sizes, depending only on the measuring convention used.

Why This Matters Beyond One Brand

None of the three methods are secret or hidden — they are simply different published standards. The rib cage method is the one that measures the band at the point it physically sits on the body, without a shortcut or an assumption about fabric stretch layered on top. BRABAR designs every product around this standard, in band sizes 28 through 38 and cups A through DDD/F, specifically because that range is the one most underserved by the plus-4 and armpit conventions.

Frequently Asked Questions

Why is my BRABAR size different from my Victoria's Secret size?

Victoria's Secret's instructions measure higher on the torso, near the armpit, which produces a larger band number than measuring directly at the rib cage.

Why is my BRABAR size different from my SKIMS or Aerie size?

SKIMS and Aerie's calculators add four inches to your underbust measurement before calling it a band size. BRABAR's EZ-fit method uses the direct rib cage measurement with nothing added.

Which method is correct?

The rib cage method measures the band at the point where it physically sits on the body, without adding inches or shifting the measurement point higher on the torso, which makes it the most anatomically direct of the three.

Can I convert between the different sizing methods?

Not reliably, because each method starts from a different band measurement. The most accurate approach is to re-measure using the rib cage method directly rather than converting a size found under a different system.

Find your size with BRABAR's Fit Guide and Bra Size Calculator, and explore our full range of band and cup sizes, built around the rib cage method from the ground up.