No Pad,
No Problem
5 Reasons to
Switch to Knix
Leakproof Undies
5 Reasons to Switch to Knix Leakproof Undies
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1.
They're Ultra Absorbant
They absorb up to 2 tampons worth of liquid. Wear them worry-free on light days or as backup protection for heavy ones.
2.
They’re Anti-Odor!
We use carbon cotton as a chemical-free antimicrobial agent, eliminating any odor between washes.
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3.
They Keep You Dry
Fabric wicks moisture away from your skin, dries 2-3x faster, and prevents anything from leaking through to your clothes.
4.
They’re Machine Washable
Just toss them in your handy Knix lingerie wash bag. Wash them on cold, and lay flat to dry. Quick and easy.
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5.
Bye-Bye, Panty Lines!
They’re totally seamless, so they stay undetectable under even the tightest leggings.
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Catalyst Bra Sizing
Fits snug at first, relaxes after 1 wear.
Your Bra Size
Knix Size
PumpEase Bra Sizing
Your Bra Size
PumpEase Bra Size
Leakproof Nursing Bra Sizing
Your Bra Size
Knix Size
Leakproof Pads Sizing
Cups
M A-D
XL DD-G
Longevity Bra Sizing
Band (in) Band (cm)
S 32" 81cm
M 34" 86cm
L 36" 91.5cm
XL 38" 96.5cm
Sizing
Your Bra Size
Knix Size
Your Bra Size
Knix Size
The Every Bodysuit Sizing
Band (in) Band (cm)
S 32" 81cm
M 34" 86cm
L 36" 91.5cm
XL 38" 96.5cm
XXL 40" 101.6cm

*Bodysuits fit up to a DD cup.

Racerback Sizing
Band (in) Band (cm)
S 32" 81cm
M 34" 86cm
L 36" 91.5cm
XL 38" 96.5cm
XXL 40" 101.6cm

*Cup ranges from A-DD

Underwear
Hips (in) Hips (cm) Pant
S 33"-37" 84-94 2-6
M 38"-41" 96-104 8-10
L 42"-44" 106-112 12-14
XL 45"-47" 114-120 16-18
XXL 48"-50" 122-128 20-22
One Piece
Band (in) Fits Cups
S 32" A-DD
S+ 32" E-G
M 34" A-DD
M+ 34" E-G
L 36" A-DD
L+ 36" E-G
XL 38" A-DD
XL+ 38" E-G
XXL 40" A-DD
XXL+ 40" E-G
One Piece
Band (in) Fits Cups
S 32" A-DD
S+ 32" E-G
M 34" A-DD
M+ 34" E-G
L 36" A-DD
L+ 36" E-G
XL 38" A-DD
XL+ 38" E-G
XXL 40" A-DD
XXL+ 40" E-G
Don't Sweat It T-Shirt
Bust (in) Natural Waist (in) Hips (in)
S 33"-35" 26"-28" 36"-38"
M 36"-37" 29"-30" 39"-40"
L 38"-40" 31"-33" 41"-43"
XL 41"-43" 34"-36" 44"-46"
XXL 44"-45" 37"-38" 47"-48"
XXXL 46"-48" 39"-41" 49"-51"
Sleep Set
Bust Waist Hip
S 34" 27" 37"
M 37" 30" 40"
L 40" 33" 43"
XL 43" 38" 46"
XXL 47" 43" 50"
XXXL 51" 48" 53"
Socks Sizing
US UK EU
S 6-8 3.5-5.5 36-38.5
M 8.5-10 6-7.5 39-42
How To Measure
Our bras will fit a bit differently than you’re used to, so we encourage you to use the guide below to find your perfect size.

Please wear an unpadded or lightly lined bra while taking these measurements (compression bras and padded bras will alter the results).
Band Size (Ribcage measurement)
Measure snugly around your ribcage, directly under your bust. Add 2” to your underbust measurement, & round up to the closest even number.
31” + 2” = 33”, rounded up to 34” Band size = 34”
Cup Size (Full bust measurement)
Wrap the measuring tape snugly around the fullest part of your bust. Compare yourfull bust measurement to the ribcage measurement that you took (please use the initial measurement result before adding two inches or rounding up to the nearest even number). For every inch difference, add a cup size.
31” ribcage measurement & 36” across-bust measurement = 5” difference
Go up 5 cup sizes. Cup size = 34DD
Cup Size Guide
Bra Size Chart
Your Bra Size
Knix Size
Band (in) Band (cm)
S 32" 81cm
M 34" 86cm
L 36" 91.5cm
XL 38" 96.5cm
XXL 40" 101.6cm
Leakproof Bikini
What Women Are Saying About Knix Leakproof
"Ordering more to replace all of my underwear!"
Carol W.
"Easy to wash and quick to dry which is a great plus for traveling."
Babette P.
"They saved me the very first time I wore them."
Laura H.
"They’ve changed my period game. Wish I had have bought them sooner but glad I did now. I’ll never go through another period without them!"
Abigail V.
"These fit well and have a sleek design. The material is very soft. I used them on a hot day doing yard work & it was so much better than feeling a sweaty pad!"
Amy D.
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