This post will serve as a starting point for your sizing. We use UK sizing, so keep that in mind when selecting a cup size.
BAND SIZE
Measuring for your bra size is very straightforward. You may want to have someone to help you do it if you can, but you can do it yourself too and be just as accurate. I suggest measuring yourself in front of a mirror. You’ll only need a soft measuring tape, and I suggest you wear a well-fitting, soft-cup, wired bra. If you don’t have one, you can do this braless as well.
Using the soft measuring tape, wrap it snugly around your underbust (the area directly beneath your breasts, where a bra band would sit) and pull firmly but comfortably. I always tell people to pull the amount of snugness they’d want from a bra band – firm and supportive, but not painful or uncomfortable. Like a hug. Make sure your arms are lowered and at your side, as lifting your arms will skew the measurement.
We use the +0 method, meaning that we don't add inches to our underbust measurement to get our band measurement.
Record the number you got from your underbust measurement. If you measure 36", you'd take a 36 band.
If your underbust measures as an odd number or a fraction, use discretion to round up or down to the nearest even number depending on how snug you want your band to fit.
CUP SIZE
Wrap the tape measure around the fullest part of your bust, ensuring that you don't pull. If your breasts are not self-supporting, you are braless, or are more pendulous in shape, you may want to lean forward to get this measurement. If there is a drastic difference between your standing bust measurement as opposed to if you leaned forward, record the larger one.
Next, all you need to do is take the smaller number (your underbust measurement) and subtract it from the larger number (your bust measurement). Each inch of difference you have corresponds to a cup size. Consult the chart below.
| Difference, Inches | Cup Size, UK |
| 1" | A |
| 2" | B |
| 3" | C |
| 4" | D |
| 5" | DD |
| 6" | E |
| 7" | F |
| 8" | FF |
| 9" | G |
| 10" | GG |
| 11" | H |
Mind you, cup sizes can go up to an L cup, so this chart doesn't show all of them. But these sizes are where our patterns are primarily focused.
I want to reiterate that this may only be a starting point. If you typically wear one size and you're happy with it, and you measure as another, keep wearing what you're happy with, as these are merely guides.
