All Underwear

Save 10% on 3-4 pairs of Any Underwear
Save 15% on 5-6 pairs of Any Underwear
Save 20% on 7+ pairs of Any Underwear
(excludes Last Call & Sale items and Pre-discounted Kits)

Super Absorbency
A total replacement for disposable period products - absorbs approximately 8 tsp, 40 ml, or the equivalent of 8 regular tampons worth of liquid.

High Absorbency
Ready to stop leaks whenever - absorbs approximately 4-6 tsp, 20-30 ml, or the equivalent of 4-6 tampons worth of liquid.

Medium Absorbency
Confident backup protection for heaviest days - absorbs approximately 3 tsp, 15 ml, or the equivalent of 2 tampons worth of liquid.

Light Absorbency
Protection for your lighter days - absorbs approximately 1 tsp, 5 ml, or the equivalent of 1 tampons worth of liquid.

Our Leakproof Period Underwear feature barely-there built-in panty liners that can absorb between 1 and 8 tampons worth of liquid, providing you with confident protection against period leaks, light bladder leaks, and sweat.

Our Essential Underwear feature a moisture-wicking breathable gusset that keeps sweat and odor away, but they do not provide any leakproof protection.

If you want help finding the perfect Leakproof period underwear product size for you, connect with one of our expert Knix team members for a 1-on-1 fitting session over video chat. Book a time that’s convenient for you, and we’ll walk you through everything!

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Our Cotton Modal is a fabric blend made up of naturally breathable cotton and super soft modal fabric. Modal is an eco-friendly fabric made from regenerative plants, produced using less water and fewer chemicals, with properties very similar to Cotton. While our other Leakproof Underwear are made with synthetic fabrics and are totally seamless, our Cotton Model Underwear do have some stitching.