HOW TO DETERMINE YOUR SPORTS BRA SIZE

HOW TO DETERMINE YOUR SPORTS BRA SIZE

All women’s bodies are beautiful, worthy, and deserving of the right support! The right sports bra is our freedom, and our essential equipment.

Follow our Three Easy Steps below - to determine your bra size. 

A few things to consider when selecting a sports bra:

Bodies change over time.

Our bodies change more than we think — with potential for dramatic differences over a lifetime. Many factors can contribute to breast changes, including puberty, weight gain/loss, pregnancy, breastfeeding, illness, surgeries (including reduction, augmentation, or gender affirming procedures), hormone therapy, exercise, nutrition, etc. This is normal. The key is to remember that just as your life changes, so do your sports bra needs.

Sizing is variable by brand.

Sports bra sizing by manufacturer is highly variable. Unfortunately, the industry hasn’t done us any favors, and there is no true, universally accepted sizing system. There are some industry standards, and ours adhere to those (explained below). Your best bet is to find the brand and sizing that works the best for you. We feel confident you’ll find something you love in Oiselle’s full spectrum of sports bras.

Personal preferences matter.

Everyone’s preferences are different! For example, when it comes to sports and running bras, some women prefer a locked down feeling with their sports bra, and some prefer more ease of movement. Those preferences should also be factored in when choosing a sports bra type and size.

Follow the steps below to determine your sports bra size.

With a measuring tape, measure the total circumference of your rib cage, front and back, just under your breasts. The measuring tape should be even, and not pulled too tight. Write this measurement down. This is your FIRST measurement and is your RIB CAGE SIZE.

This is the step that throws most people off! Note that your rib cage measurement is NOT the same as your bra band size. Due to archaic bra sizing, it is industry standard to ADD 4-5” to your rib cage measurement to get your band size (for more info, read this). Use this chart to find which range your rib cage measurement falls within, and THEN note the corresponding band size to the right. This is your SECOND measurement to write down. This is your BAND SIZE.

Measure the total circumference of your bust, which is around your chest at the widest part. This is your THIRD measurement and your BUST SIZE. Subtract your RIB CAGE SIZE from your BUST SIZE. That number will determine your CUP SIZE. Using the chart to the left, find your cup size based on that number.

Example: Alana’s rib cage is 30 inches (thus a 34 band). Her bust measurement is 35 inches. 35 (BUST) minus 30 (RIB CAGE) equals 5” which equals a DD cup. Alana is a 34DD.

Tips on Fit and Sports Bra Construction

Build that base. The chest band of the sports bra is your foundation. It should fit snugly, but not too tight around your body. The chest band line, front and back should be straight. Tip: if you notice the band pulling up in the back, it’s likely too small.

Stable straps. For larger cup sizes, it’s important for shoulder straps to be padded and soft, but to not stretch too much. Stretchy straps create a slingshot effect in high impact sports, causing more bounce.

Avoid top bounce. During high impact exercise, breasts are like escape artists. They’ll move wherever there’s less support. While cleavage is awesome for lots of things, it’s not great for running, causing pain or merely detracting from a workout. Tip: Make sure your sports bra is supporting you from all angles, bottom, side, and top.

Look for spillage. If you notice breast tissue coming out of the top of the sports bra, sides, or being pinched in the band, chances are you need a larger cup size. If the fit of the current band is good, increase cup size only. For example, go from a 36D to a 36DD.

When breast sizes are different. A difference in size between breasts is common. Fit the sports bra to the larger breast, and choose a bra with light padding and/or strong compression fabric so that both breasts are supported. Your size will change. Breast sizes can vary quite a bit over time. It's common for women to have 6-7 different bra sizes over their lifetime, so make sure to measure yourself, or get a bra fitting every year.

Remember: nothing should stand between you and your ability to feel strong and free!

Have questions about sizing, fit, or support levels?

Wondering which Oiselle sports bra is right for you?

We’re here to help. Email hello@oiselle.com and we’re happy to guide you through determining your size, and finding the right sports bra for your needs.

— Sally Bergesen
Tagged: style
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