What you need to know this instant.

Do You Wear the Same Bra Size in Every Brand? We Measure Styles From Five Labels to Find Out

To make sure your bras are comfortable, it's really important to get fitted by a specialist at least once a year. The rest of the time, ordering online is completely okay—albeit a little trickier. Band widths vary slightly depending on the company, so you never know how a new label will fit.

To help figure out which size you are at what brand, we measured the end-to-end length of T-shirt bras from five popular lingerie lines—Calvin Klein's Level 3 Seductive Comfort Customized Lift, Victoria's Secret's Full Coverage, Gap's Favorite T-Shirt, Bali's Back To Beautiful and Elle MacPherson's Bare & Bold—to compare proportions. Consult the charts below to see how you size up. (Or down!)

A Cups

Most of the A-cups were the same size, but Gap Body gives about an extra half-inch for the 32A and 34A. And all of the Calvin Klein styles run small by two or three inches.

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