knix

20M+ Pairs Sold

Life-changing Leakproof underwear
  • ✓ For periods, pee, sweat, & discharge.
  • ✓ Absorbs up to 11 super tampons.
  • ✓ Machine washable & reusable.
Find my perfect pairSee how it works
Patented 360°Fresh Fix Technology®
Inclusive SizingXS–4XL
Free Shippingover $65
30-Day GuaranteeFirst pair risk-free
Meet your Leakproof Bestie

Answer a few quick questions and get a personalized match in under 60 seconds.

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Knix Leakproof Bestie
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#1 Leakproof Brand in North America
#1 Leakproof Brand in North America
#1 Leakproof Brand in North America
#1 Leakproof Brand in North America
#1 Leakproof Brand in North America
#1 Leakproof Brand in North America
#1 Leakproof Brand in North America
#1 Leakproof Brand in North America
#1 Leakproof Brand in North America
#1 Leakproof Brand in North America
Built-in patented protection that feels like nothing at all
Soft top layer

Wicks away moisture from your skin and fights odor.

Middle layer

Quickly soaks up the liquid that's moved down from the top layer.

Leakproof layer

Seals in liquid discreetly, so leaks can't reach your clothes or sheets.

360
360° leakproof edges

Our patented Fresh Fix Technology® locks in leaks at every edge.

★★★★★ Everyone's switching to Knix Leakproof

+20 million pairs sold. And counting...

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★★★★★ Life changing! My flow was so heavy, but I felt covered by these panties. Thank you, Knix!

— Priyanka

★★★★★ Now that I've used period underwear, I'm never going back! Pads & tampons who? Not me.

— Olivia

★★★★★ The best. I love the seamless fit. I never have to worry about leaks.

— Cynthia
Leakproof Absorbency Guide

Match your flow to the right level.

Tap a tier to see what's best for the moment.

Best Selling Leakproof

Our top picks — loved by millions.

Leakproof CoreLove High Rise
Leakproof CoreLove High Rise
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UltraThin No-Show High Rise
UltraThin No-Show High Rise
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Light Leakproof No-Show High Rise
Light Leakproof No-Show High Rise
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Super Leakproof Cotton High Rise
Super Leakproof Cotton High Rise
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SuperPlus Leakproof No-Show High Rise
SuperPlus Leakproof No-Show High Rise
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See all best sellers
Your underwear questions, answered.
How do I wash them?

Rinse cold after wear, machine wash cold on gentle, air dry. That's it — no special detergent, no handwashing. Just like your regular underwear.

Do I need a pad or tampon with leakproof underwear?
No — leakproof underwear is designed to replace them entirely. Match your absorbency level to your flow. Ultra holds up to 11 super tampons; skip the backup for good.
What's the 30-day guarantee?
Your first pair is risk-free for 30 days. Wear it, wash it, test it. If it's not right, send it back for a full refund — no questions asked.
How many pairs do I need for a full cycle?
Most people start with 5-7 pairs. Enough to rotate through a full cycle with time for washing. Heavier flows may want a mix of absorbency levels — Heavy/Ultra for peak days, Light/Moderate for the tail end.
Which styles have the most coverage?
High Rise and Boyshort offer the most coverage. Dream Short has an extra-long liner (10-14") for maximum protection. Thongs and Bikinis give standard coverage in a smaller silhouette.
What is Leakproof technology?
A built-in, patented absorbent liner (gusset) sewn into the crotch of the underwear. Three layers — moisture-wicking top, absorbent core, leakproof barrier — handle periods, sweat, light bladder leaks, and discharge without a pad or tampon.