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10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

10k+ 5-star reviews

Sleep through the night, even on your heaviest days

Leak-proof, comfortable overnight period underwear trusted by 10,000+ 5-star reviewers.

Sleep through the night, even on your heaviest days

Leak-proof, comfortable overnight period underwear trusted by 10,000+ 5-star reviewers.

Kt. Best Sellers

First Period Kit - Bikini

Light - Heavy Absorbency

-

$144 ^USD $192 Save 25%

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Heaviest Absorbency Yet

+1

Super Leakproof® Sleepover Boxer

Heavy Absorbency

$45 ^USD Back in Stock

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+5
+1

Period Swim Sport One-Piece

Moderate Absorbency

$88 ^USD New Colors

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+7
+3

Super Leakproof® Sleepover Short

Heavy Absorbency

$45 ^USD 2 for $39 EACH

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+4

Period Swim Bikini Bottom

Moderate Absorbency

$45 ^USD New Colors

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+3

Period Swim Full-Coverage Bikini Bottom

Moderate Absorbency

$45 ^USD New Colors

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+7
+3

Leakproof UltraThin No-Show Underwear Boyshort 3-Pack

Moderate Absorbency

$65 ^USD $72 New Colors

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+2

Period Swim Short

Moderate Absorbency

$55 ^USD New Colors

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+6
+2

Light Leakproof No-Show Underwear Bikini 3-Pack

Light Absorbency

$60 ^USD $66 New Colors

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New Innovation + Absorbency

+1

Super Leakproof® No-Show Underwear Bikini

Heavy Absorbency

$27 ^USD 3+ for $25 EACH

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1 in 2 teens misses out on swimming because of their period

Period swim keeps them active without having to worry about excuses to sit out, intimidating tampons, or embarrassing period leaks.

1 in 2 teens misses out on swimming because of their period

Period swim keeps them active without having to worry about excuses to sit out, intimidating tampons, or embarrassing period leaks.

Machine Washable

Machine Washable

Machine Washable

Machine Washable

Machine Washable

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Machine Washable

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Machine Washable

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Buy 3+ & Save

New Innovation + Absorbency

+1

Super Leakproof® No-Show Underwear Bikini

Heavy Absorbency

$27 ^USD 3+ for $25 EACH

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+4

Light Leakproof No-Show Underwear Bikini

Light Absorbency

$22 ^USD 3+ for $20 EACH

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+3

Leakproof UltraThin No-Show Underwear Bikini

Moderate Absorbency

$24 ^USD 3+ for $21.60 EACH

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+5
+1

Light Leakproof No-Show Underwear Boyshort

Light Absorbency

$22 ^USD 3+ for $20 EACH

View

Leakproof Cotton Underwear Bikini

Moderate Absorbency

$22 ^USD 3+ for $21.60 EACH

View

New Innovation + Absorbency

+1

Super Leakproof® No-Show Underwear Boyshort

Heavy Absorbency

$27 ^USD 3+ for $25 EACH

View

+3

Leakproof UltraThin No-Show Underwear Bikini

Moderate Absorbency

$24 ^USD 3+ for $21.60 EACH

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Read The Rag

Free Period Guide

Everything your teen ever wanted to know about puberty, menstruation, and more.

Download the Guide

“With this new line, teens can lean into that life well lived from their very first period”

"KT by Knix is aimed at both helping teen girls deal with the reality of periods"

“KT by Knix products are simple and easy to use — you can wear them under absolutely anything”

Teen Underwear Size Chart

KT Period Underwear is designed for smaller and growing bodies to fit teens and tweens

For adult sizes and styles, check out Knix .

KT Size	Hips	Kids Pant Size	Adult Pant Size
XXS	25” - 27”	7	---
XS	28” - 30”	8 - 10	---
S	31” - 34”	12 - 14	00 - 2
M	35” - 38”	16 - 20	4 - 8
L	39” - 42”	---	10 - 14
XL	43” - 46”	---	16 - 18
XXL	47” - 50”	---	20 - 22

Find the Perfect Fit

1. Hips

Stand with your feet together and measure around the widest part of your hips and bottom. Keep the measuring tape parallel to the floor.

Still Not Sure What Size To Get?

Book a Virtual Fitting with a team member and get 1:1 help over video chat.

Teen Swimwear Size Chart

KT swimsuits are designed for smaller and growing bodies to fit teens and tweens

For adult sizes and styles, check out Knix .

KT Size	Band	Hips	Kids Pant Size	Adult Pant Size
XXS	23 ³/₄" - 25 ¹/₄"	25” - 27”	7	---
XS	25 ¹/₄" - 26 ³/₄"	28” - 30”	8 - 10	---
S	26 ³/₄" - 28 ¹/₄"	31" - 34"	12 - 14	00 - 2
M	28 ¹/₄" - 29 ³/₄"	35” - 38"	16 - 20	4 - 8
L	29 ³/₄" - 31 ¹/₂"	39” - 42”	---	10 - 14
XL	31 ¹/₂" - 33 ¹/₂"	43” - 46”	---	16 - 18
XXL	33 ¹/₂" - 35 ¹/₂"	47” - 50”	---	20 - 22

Find the Perfect Fit

1. Band

First, measure around the torso right below the breast

2. Hips

Stand with your feet together and measure around the widest part of your hips and bottom. Keep the measuring tape parallel to the floor.

Still Not Sure What Size To Get?

Book a Virtual Fitting with a team member and get 1:1 help over video chat.

Teen Activewear Size Chart

KT activewear is designed for smaller and growing bodies to fit teens and tweens

For adult sizes and styles, check out Knix .

KT Size	Hips	Kids Pant Size	Adult Pant Size
XXS	25” - 27”	7	---
XS	28” - 30”	8 - 10	---
S	31” - 34”	12 - 14	00 - 2
M	35” - 38”	16 - 20	4 - 8
L	39” - 42”	---	10 - 14
XL	43” - 46”	---	16 - 18
XXL	47” - 50”	---	20 - 22

Find the Perfect Fit

1. Hips

Stand with your feet together and measure around the widest part of your hips and bottom. Keep the measuring tape parallel to the floor.

Still Not Sure What Size To Get?

Book a Virtual Fitting with a team member and get 1:1 help over video chat.

Teen Leotard Size Chart

KT leotards are designed for smaller and growing bodies to fit teens and tweens

For adult sizes and styles, check out Knix.

KT Size	Band	Hips
XS	28"	25” - 27”
S	30"	28” - 30”
M	32"	31” - 35”
L	34"	36” - 40”
XL	36"	41” - 44”
XXL	38"	45” - 48”

Find the Perfect Fit

1. Band

First, measure around the torso right below the breast

2. Hips

KT Leotards are designed to sit on the hips, so measure around the widest part of the hips and refer to the chart above to find the best fit.

Still Not Sure What Size To Get?

Book a Virtual Fitting with a team member and get 1:1 help over video chat.

Teen Sweatshirt Size Chart

Size	Bust	Hips
XS	27”	25" - 27"
S	30”	28" - 30"
M	34"	31" - 35"
L	37”	36" - 40"
XL	40”	41" - 44"
XXL	40”	45" - 48"

Still Not Sure What Size To Get?

Book a Virtual Fitting with a team member and get 1:1 help over video chat.

Freestyle Leakproof Tights Size Chart

Size	Hips	Height	Weight
XS/S	25" - 30"	4'2" - 5'1"	65 - 100 lbs
M/L	31" - 40"	4'9" - 5'6"	105 - 130 lbs
XL/XXL	41" - 48"	4'11" - 5'6"	135 - 170 lbs

Still Not Sure What Size To Get?

Book a Virtual Fitting with a team member and get 1:1 help over video chat.

Thigh Savers Size Chart

KT Products are designed for smaller and growing bodies to fit teens and tweens

For adult sizes and styles, check out Knix .

KT Size	Hips	Kids Pant Size	Adult Pant Size
XXS	25” - 27”	7	---
XS	28” - 30”	8 - 10	---
S	31” - 34”	12 - 14	00 - 2
M	35” - 38”	16 - 20	4 - 8
L	39” - 42”	---	10 - 14
XL	43” - 46”	---	16 - 18
XXL	47” - 50”	---	20 - 22

Find the Perfect Fit

1. Hips

Stand with your feet together and measure around the widest part of your hips and bottom. Keep the measuring tape parallel to the floor.

Still Not Sure What Size To Get?

Book a Virtual Fitting with a team member and get 1:1 help over video chat.

Bras Size Chart

KT Products are designed for smaller and growing bodies to fit teens and tweens

For adult sizes and styles, check out Knix .

Size	Under Bust (in)	Fits Cups
S	26 3/4” - 28 1/4”	A-DD
M	28 1/4” - 29 3/4”	A-DD
L	29 3/4” - 31 1/2”	A-DD