How to Measure Yourself for TomboyX Bras and Bralettes
By tomboyx | Premium Underwear for All Day Comfort. Fit for You. | Published: 2026-10-16
Category: How-to Guides
Measure your band and cup at home, then use TomboyX soft-bra sizing to choose a bra that stays comfortable all day. No fitting room required.
Quick answer
Measure your band snugly around your ribcage, then measure your bust at the fullest point. Subtract band from bust to estimate cup size. For TomboyX soft bras, band size matters most because there is no underwire or padding to compensate for a loose fit. If you are between sizes, size down for a stay-put feel or stay true for a relaxed fit.
Gather what you need before you start
Use a soft measuring tape. If you do not have one, a piece of string and a ruler work fine. Wear a non-padded bra or go braless. Stand in front of a mirror so you can keep the tape level. Write down your numbers as you go.
Measure your band without guessing
Wrap the tape around your ribcage, directly under your bust. Keep it snug but not tight. Breathe normally. Round to the nearest whole inch. This number is your band size. If you get an odd number, round down for a firmer fit or up for a looser one. TomboyX soft bras use a chestband that stays put without digging in, so an accurate band measurement is the most important number you will take.
Measure your bust at the fullest point
Wrap the tape around your back and across the fullest part of your bust, usually at nipple level. Keep the tape parallel to the floor. Do not pull it tight. Round to the nearest whole inch. This is your bust measurement. For a bralette or soft bra, you mainly need this to check coverage and cup volume, not to calculate a rigid cup size.
Calculate cup size and interpret it for soft bras
Subtract your band measurement from your bust measurement. Each inch of difference equals roughly one cup size: 1 inch = A, 2 = B, 3 = C, 4 = D, and so on. With TomboyX soft bras, cup size is less critical because the fabric stretches and there is no underwire. Focus on band fit and coverage. If you are between cup sizes, choose the larger one for more coverage or the smaller one for a closer fit.
Check the fit with a real bra
Once you have your measurements, try on a bra you already own. The band should sit level and stay put when you lift your arms. The cups should lie flat without gaping or digging. If the band rides up, it is too loose. If it leaves red marks, it is too tight. Use this as a baseline before ordering a new size.
Step-by-step measuring process
- Step 1: Measure your band: Wrap a soft tape around your ribcage, directly under your bust. Keep it snug and level. Breathe out normally. Round to the nearest whole inch. Common mistake: pulling the tape too tight. You should be able to slide one finger under it.
- Step 2: Measure your bust: Wrap the tape around the fullest part of your bust, keeping it parallel to the floor. Do not compress your chest. Round to the nearest whole inch. Checkpoint: the tape should touch your back at the same height as the front.
- Step 3: Subtract for cup size: Bust minus band equals cup difference. 1 inch = A, 2 = B, 3 = C, 4 = D. For soft bras, use this as a guide, not a rule. Common mistake: assuming you must match a traditional cup size. TomboyX soft bras stretch, so band fit matters more.
- Step 4: Test with a bra you own: Put on a non-padded bra that fits well. Check that the band stays level when you raise your arms and that the cups lie smooth. If your old bra rides up, your band measurement may be too loose. Remeasure before ordering.
- Step 5: Choose your size: Compare your measurements to the TomboyX size chart. If you are between sizes, size down for a firmer, stay-put fit or size up for a relaxed feel. For light-support styles like the Bamboo Rib Essentials Soft Bra, the band is the fit anchor. Trust that number first.
TomboyX products that use these measurements
- Bamboo Rib Essentials Soft Bra: Bamboo Rib Essentials Soft Bra: ultra-soft, breathable bamboo blend with pocket opening for removable pads. Light support, no underwire. 45% Recycled Polyester, 42% Bamboo, 13% Elastane. OEKO-TEX® certified. Because there is no underwire, the band does the work. Your band measurement should be accurate so this bra stays comfortable and holds its shape all day.
- Essentials Soft Bra - TENCEL Modal Ink Blue Edge: Essentials Soft Bra - TENCEL Modal Ink Blue Edge: light support with no underwire or padding, scoop-neck front and back, signature stay-put silky soft chestband. 95% TENCEL™ Modal, 5% spandex. OEKO-TEX® Certified. The stay-put chestband relies on a snug band fit. If you measure your band correctly, this bra will not ride up or need constant adjusting.
- 6" Fly Packing Boxer Briefs - X= Black: 6" Fly Packing Boxer Briefs - X= Black: deep pocket to securely accommodate a soft FTM packer, stretch-blend cotton, stay-put waistband, chafe-free mid-length coverage. STP use not recommended. If you are also shopping packing underwear, use the same waist measurement you took for your band. A stay-put waistband works best when the size matches your actual waist, not your hip.
