How It Works

Be the Boss of your Period.

We created Knixteen ‘Oh-No’ Proof Underwear because we believe your period shouldn’t stop you from doing awesome stuff. We’re your back-up protection against inevitable leaks, odor, and moisture, meaning you can stay confident no matter what time of the month it is. Whether you’re bringing your period to school, the big soccer game, the movies, or a sleepover – bring us too.

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What are Knixteen period panties?

Our Oh No’ Proof Underwear are designed by people who have periods, for people who have periods. They prevent embarrassing leaks and unwanted smells, keeping you confident and comfortable when Aunt Flo comes to visit.

How does Knixteen period underwear work?

Our ‘Oh-No’ Proof Underwear has absorbent technology in the gusset (that panel of fabric between your legs), which allows the underwear to absorb extra blood and moisture, preventing leaks!

What do other reviews say about Knixteen period underwear?

We don’t like to sing our own praises… so we let these real teens and tweens do it for us!

Can Knixteen period underwear replace pads?

Knixteens are designed to provide backup support when your tampon, pad or menstrual cup just isn’t enough. Our undies hold 2-3 teaspoons of moisture (aka 2 tampons worth of blood), so they can be worn alone on lighter days of your period - just depends on your cycle.

Can I only wear my Knixteens when I’m on my period?

Our ‘Oh-No’ Proof Underwear is seamless, sweat-wicking and odor-crushing. You can wear them under leggings and not worry about unwanted panty lines, or you can wear them during your workout to keep yourself smelling fresh as a daisy. Plus, they’re super comfy. Basically, you can wear your Knixteens 24/7 if you want to - we won’t judge.

Can you swim in Knixteen period panties?

Unfortunately not. Knixteen underwear is so good at its job that it’ll absorb everything - including water! Stick to tampons or menstrual cups instead when you go swimming on your period, and be sure to bring a few backups along just in case.

Does it feel like you’re sitting in a puddle?

Not at all! In fact, many teens have told us our underwear feels drier than regular disposable pads. This is thanks to our quick-drying and moisture-wicking technology!

What size do I get?

Our underwear is made in junior sizing, to fit teens bodies. Everyone’s body is different, so refer to the Knixteen size chart to find your best fit. If you’re not a teen but you’re loving the idea of added protection for leaks, check out our adult line Knix!

How do you wash Knixteen period panties?

Just toss them in the wash with the rest of your clothes and hang to dry! Don’t worry about blood getting on your other clothes in the wash, they’ll be just fine. If you’re a worry wart, give your Knixteens a quick rinse in the sink before you throw them in the wash.

Are Knixteen period panties safe?

Super safe! Our period-proof underwear is 100% hygienic and made to be up close and personal with the most sensitive areas of your body.

What is Knixteen period underwear made from?

The body of our undies is made from 77% nylon and 23% LYCRA®. The gusset liner (the piece of fabric between your legs) is made from 86% cotton, 10% spandex and 4% carbon. Our gusset features our very own ‘Oh-No’ Proof Technology™ to keep you fresh and leak-free!

How do I return them?

Since our product comes in close contact with a very sensitive, private area of your body, we do not accept returns. However, if you are unsatisfied with your order, send us an email at and we will do our best to resolve the issue.

Where do you sell them?

Our product is available exclusively online at or