Find My Fit
Find your fit
Most bras don’t fit because most sizing is a guess. Here’s how to find yours — properly, in plain language, no measuring-tape anxiety required.
“XL” isn’t a size.
Your ribcage and your bust are two different measurements — which is exactly why a real size has a number and a letter: a band and a cup. “S / M / L / XL” throws that away and hopes for the best.
That’s why so much “plus” underwear and so many “comfort” bras never quite work: they were never measuring the right things. We start where the fit actually lives.
Two numbers. One that actually fits.
The band wraps your ribcage and does most of the support. The cup holds your bust. Get both right and the whole day changes.
Three quick steps.
Your band
Wrap a soft tape snugly around your ribcage, right under your bust, level all the way around. That number, rounded, is your band size.
Your bust
Measure loosely around the fullest part of your bust, tape level and relaxed — no pulling tight.
Your cup
The difference between bust and band is your cup. Bigger difference, bigger cup — it’s that simple. Use the chart below.
Match your measurements to a size.
Band — from your ribcage
| Ribcage (in) | Band size |
|---|---|
| 27–28" | 28 |
| 29–30" | 30 |
| 31–32" | 32 |
| 33–34" | 34 |
| 35–36" | 36 |
| 37–38" | 38 |
| 39–40" | 40 |
| 41–42" | 42 |
| 43–44" | 44 |
| 45–46" | 46 |
Cup — bust minus band
| Difference | Cup (US) |
|---|---|
| 1" | A |
| 2" | B |
| 3" | C |
| 4" | D |
| 5" | DD (E) |
| 6" | DDD (F) |
| 7" | G |
| 8" | H |
| 9" | I |
| 10" | J |
Example: 37" ribcage + 44" bust = a 38 band with a 6" difference → 38DDD. If you’re between sizes, try your sister size — go down a band and up a cup (or up a band, down a cup) for the same cup volume.
Underwear & shapewear — quick guide
| Soffion size | US dress | Approx. band | Hip (in) |
|---|---|---|---|
| 1X | 14–16 | 38–40 | 43–45" |
| 2X | 18–20 | 42–44 | 46–48" |
| 3X | 22–24 | 46–48 | 49–52" |
| 4X | 26–28 | 50–52 | 53–56" |
A guide, not a rule — every style notes “runs small / true / large” on its product page so you’re never guessing at checkout.
Signs your current bra doesn’t fit.
Comfort doesn’t mean no support.
Going wireless doesn’t mean giving up support. A firm band and wide, cushioned straps do the real lifting — wire is just one way to get there, and often the least comfortable one. That’s why our wireless styles genuinely support a full bust without the noon-time misery.
Still not sure of your size?
Take the 60-second Fit Test. Tell us what you wear now and what’s going wrong — we’ll point you to the right size and style.
Not medical or clinical advice — just practical fit guidance. If you have a specific medical or post-surgical need, your fitter or clinician is the best guide.