How to Measure Your Bra Size: A Step-By-Step Guide
February 7, 2024Did you know that 70% of women are wearing the wrong bra size? It’s true! Finding the right size can be confusing, but it’s essential for both comfort and confidence. Wearing the wrong size can lead to discomfort, poor posture, and an unflattering silhouette.
In this guide, we’ll show you two simple ways to measure your bra size—by using our Bra Size Calculator or following a few easy manual steps. Whichever method you choose, we’re here to help you get the support you need to feel comfortable and confident all day long!
Method 1: Use BOOMBA's Bra Size Calculator
If you'd rather skip the manual steps, try our easy-to-use Bra Size Calculator! All you need to do is input your underbust and overbust measurements, and we'll calculate your perfect bra size for you.
Measure Your Bra Size
Not sure about your BOOMBA size? Enter your measurements below to find your perfect fit!
How to get your overbust & underbust Size?
- Overbust Size. Measure around the fullest part of your bust with a bra on, keeping the tape straight.
- Underbust Size. Measure snugly around your ribcage, just under your bust, keeping the tape straight.
This tool takes out all the guesswork, ensuring that you get the most accurate fit without doing any math. Perfect for those who prefer a quick, reliable answer!
Method 2: Measure Manually at Home
What You Need
● Tape measure
● The best-fitting non-padded wired bra
● Pen and paper to write down your measurements
Step 1: Find Your Band Size
Wrap the tape measure snugly around your rib cage, directly under your bust. Be sure it’s not too tight or too loose. Round this number to the nearest whole number.
● Example: If your underbust measurement is 31 inches, add 1 inch to determine your band size.
Step 2: Measure Your Bust Size
Next, measure around the fullest part of your bust, typically across the nipple line. Keep the tape parallel to the floor, and ensure it rests comfortably on your skin—not too tight, but not too loose either.
Step 3: Calculate Your Cup Size
Subtract your band size (from Step 1) from your bust measurement (from Step 2) to determine the difference. Use the chart below to find your cup size.
● Example: If your bust size is 38 inches and your band size is 32 inches, then 38 - 32 = 6. According to the chart, a 6-inch difference means you’re a DDD/F cup.
DIFFERENCE (INCHES)
CUP SIZE
less than 1
AA
1
A
2
B
3
C
4
D
5
DD/E
6
DDD/F
7
G
8
H
9
I
10
J
11
K
12
L
13
M
14
N
15
O
16
P
17
Q
18
R
19
S
Note that this chart uses US cup sizes.
Now, combine your band size with your cup size. For example, if your band size is 32 and your cup size is DDD/F, your bra size is 32DDD/F.
How to Choose the Right BOOMBA Size
Now that you know your bra size, selecting the correct size for your BOOMBA inserts is a breeze! Simply refer to our chart below, and don’t forget to size up if you’re in between sizes to ensure the perfect fit with our inserts.
bra size
US Size
BOOMBA Bra Size
Size Category
60A
AA
X-Small
65A
AA
X-Small
70A
AA
X-Small
75A
A
X-Small
80A
B
Small
85A
C
Small
90A
D
Medium
95A
E
Medium
100A
F
Medium
US Size
BOOMBA Bra Size
Size Category
60B
AA
X-Small
65B
AA
X-Small
70B
A
X-Small
75B
B
Small
80B
C
Small
85B
D
Medium
90B
E
Medium
95B
F
Medium
100B
G
Large
US Size
BOOMBA Bra Size
Size Category
60C
AA
X-Small
65C
A
X-Small
70C
B
Small
75C
C
Small
80C
D
Medium
85C
E
Medium
90C
F
Medium
95C
G
Large
100C
H
Large
US Size
BOOMBA Bra Size
Size Category
60D
A
X-Small
65D
B
Small
70D
C
Small
75D
D
Medium
80D
E
Medium
85D
F
Medium
90D
G
Large
95D
H
Large
100D
I
Large
US Size
BOOMBA Bra Size
Size Category
60E
B
Small
65E
C
Small
70E
D
Medium
75E
E
Medium
80E
F
Medium
85E
G
Large
90E
H
Large
95E
I
Large
100E
J
X-Large
US Size
BOOMBA Bra Size
Size Category
60F
C
Small
65F
D
Medium
70F
E
Medium
75F
F
Medium
80F
G
Large
85F
H
Large
90F
I
Large
95F
J
X-Large
100F
K
X-Large
US Size
BOOMBA Bra Size
Size Category
60G
D
Medium
65G
E
Medium
70G
F
Medium
75G
G
Large
80G
H
Large
85G
I
Large
90G
J
X-Large
95G
K
X-Large
100G
L
X-Large
US Size
BOOMBA Bra Size
Size Category
60H
E
Medium
65H
F
Medium
70H
G
Large
75H
H
Large
80H
I
Large
85H
J
X-Large
90H
K
X-Large
95H
L
X-Large
100H
M
X-Large
US Size
BOOMBA Bra Size
Size Category
60I
F
Medium
65I
G
Large
70I
H
Large
75I
I
Large
80I
J
X-Large
85I
K
X-Large
90I
L
X-Large
95I
M
X-Large
100I
N
X-Large
US Size
BOOMBA Bra Size
Size Category
60J
G
Large
65J
H
Large
70J
I
Large
75J
J
X-Large
80J
K
X-Large
85J
L
X-Large
90J
M
X-Large
95J
N
X-Large
100J
O
X-Large
US Size
BOOMBA Bra Size
Size Category
60K
H
Large
65K
I
Large
70K
J
X-Large
75K
K
X-Large
80K
L
X-Large
85K
M
X-Large
90K
N
X-Large
95K
O
X-Large
100K
P
2X-Large
US Size
BOOMBA Bra Size
Size Category
60L
I
Large
65L
J
X-Large
70L
K
X-Large
75L
L
X-Large
80L
M
X-Large
85L
N
X-Large
90L
O
X-Large
95L
P
2X-Large
100L
Q
2X-Large
US Size
BOOMBA Bra Size
Size Category
60M
J
X-Large
65M
K
X-Large
70M
L
X-Large
75M
M
X-Large
80M
N
X-Large
85M
O
X-Large
90M
P
2X-Large
95M
Q
2X-Large
100M
R
2X-Large
US Size
BOOMBA Bra Size
Size Category
60N
K
X-Large
65N
L
X-Large
70N
M
X-Large
75N
N
X-Large
80N
O
X-Large
85N
P
2X-Large
90N
Q
2X-Large
95N
R
2X-Large
US Size
BOOMBA Bra Size
Size Category
60O
L
X-Large
65O
M
X-Large
70O
N
X-Large
75O
O
X-Large
80O
P
2X-Large
85O
Q
2X-Large
90O
R
2X-Large
US Size
BOOMBA Bra Size
Size Category
60P
M
X-Large
65P
N
X-Large
70P
O
X-Large
75P
P
2X-Large
80P
Q
2X-Large
85P
R
2X-Large
US Size
BOOMBA Bra Size
Size Category
60Q
N
X-Large
65Q
O
X-Large
70Q
P
2X-Large
75Q
Q
2X-Large
80Q
R
2X-Large
US Size
BOOMBA Bra Size
Size Category
60R
O
X-Large
65R
P
2X-Large
70R
Q
2X-Large
75R
R
2X-Large
US Size
BOOMBA Bra Size
Size Category
60S
P
2X-Large
65S
Q
2X-Large
70S
R
2X-Large
US Size
BOOMBA Bra Size
Size Category
60T
Q
2X-Large
65T
R
2X-Large
US Size
BOOMBA Bra Size
Size Category
60U
R
2X-Large
How to Know If Your Bra Fits Correctly
Once you’ve found your size, it's important to make sure your bra actually fits. Use this checklist to double-check the fit:
● Straps: They should rest comfortably on your shoulders without digging in.
● Band: It should be snug but comfortable, with enough room to fit two fingers underneath.
● Underwire: The underwire should sit flat against your rib cage without poking or lifting away.
● Cups: The cups should fully encase your breasts without any spillage on the sides or over the top.
Conclusion
Finding your perfect bra size doesn’t have to be complicated. Whether you prefer using our Bra Size Calculator or measuring manually, we’ve made it easy to discover the right fit. Once you know your size, shopping for bras becomes a lot more fun and less of a hassle!
Ready to shop? Explore BOOMBA products today and find your new favorites. If you need any help, don’t hesitate to reach out via email or DM—we’re always here to assist!