About Proof

Proof undies look and feel just like normal undies but have built-in, leak proof® technology.

Our Quick-Wick liner pulls moisture away from the body and into the super absorbent core. Antimicrobial fibers inhibit the growth of bacteria and reduce odor, helping you to feel fresh and dry. Leak-Loc® edges seal in leaks and prevent liquid from escaping the undies.

Wear as you would normal undies, and then machine wash and reuse again and again!

To learn more about how Proof works, keep reading.

All Proof undies feature our specially crafted leak protection – the higher the absorbency, the more layers of protection!

Here’s a quick absorbency breakdown:

- Super Light: Holds up to 1 light tampon or a pantyliner
- Light: Holds up to 1 Regular Tampon or 2 Teaspoons
- Moderate: Holds up to 3 Regular Tampons or 6 Teaspoons
- Heavy: Holds up to 4 Regular Tampons or 8 Teaspoons
- Super Heavy: Holds up to 5 Regular Tampons or 10 Teaspoons

You can shop by absorbency here.

We typically suggest buying your normal undie size. Some styles run a tad bit roomier, so be sure to check out our size guide and reviews by style to find your best fit!

Proof undies are designed for comfort and all-day wear. Our Super-Light, Light and Moderate undies feel just like your favorite pair of regular underwear. Our Heavy and Super-Heavy styles may feel slightly more substantial due to their highly absorbent construction, but they will still feel super comfortable.

Most importantly, you’ll love the extra protection.


Yes! One of the biggest benefits of switching to Proof is that our ultra absorbent undies are machine-washable and reusable, so you can use them again and again.

Not only does this keep single-use plastic period and incontinence products out of landfills and oceans, but can save you money over the lifetime of your Proof undies. Talk about a win-win!

Proof undies feature strong protection, but should be washed gently. Simply toss in the washing machine on a delicate cycle, using cold water and mild detergents. Hang or lay flat to dry.

To learn more about how to care for your pair, keep reading. 

Depending on absorbency level and humidity level, Proof undies can take between 6 and 24 hours to dry. To expedite the drying process, blot away excess moisture before laying flat or hang drying. 

Just like most intimates, how long they last depends on how well you care for them. Proof undies are comparable with other undies and last between 2-3 years on average. Be sure to follow our care instructions to help your  undies last even longer.  

Proof undies are equipped with moisture-wicking lining and antimicrobial fibers that inhibit the growth of bacteria and reduce odor.

If you want to refresh and sanitize your undies, simply add a few drops of vinegar or tea tree oil to your washing machine during the rinse cycle and complete washing as normal. Voila! So fresh and so clean.

Leak Types

Proof is great for periods and bladder leaks, as well as discharge, sweat, spotting, maternity and postpartum leak protection, and even everyday wear!

Our undies can replace panty liners and pads, and replace or back up a tampon or menstrual cup. In essence, we've got everything here for anything going on down there. 

You can shop by leak type here.

In a word, yes!

Our super heavy styles hold 5 tampons or 10 teaspoons of liquid, and have been able to lock in even the heaviest flows.

If you're unsure about switching to Proof completely, you may feel more comfortable using Proof undies as a back-up for your menstrual cup or tampon.

Some of our period best sellers are The Bikini, The Mesh Hipster, and The Hipster, which handles even the heaviest flows! To find the best style for your period, shop by absorbency.

Proof is perfect for everyday wear, so you’re always protected. The Everyday Undie and Thong are ideal for day-to-day wear for any of life’s little leaks. You can shop by leak type here.

Yes! Proof underwear were specifically designed for all of life’s little leaks. Our Super-Heavy styles hold up to 10 teaspoons of liquid! Shop for bladder leaks here.

Proof is every new mama’s best friend for all of those unexpected pregnancy and postpartum leaks!

We recommend the Everyday Undie, the Lace Cheeky, or The Brief for ultimate comfort and a lower rise to accommodate your growing bump.

And don’t forget to grab Proof undies for after baby – no more mesh hospital underwear! We’ve got you covered. 

Shop maternity styles and postpartum favorites.

Customer Service

While we try to keep our shelves well-stocked, sometimes a style is so popular that it sells out! 

If you're loving a style that's out of stock, you can sign up for alerts to be notified as soon as more inventory arrives. Choose the style, color, and size you would like, and select 'Notify When In Stock' then enter your email address and phone number to be alerted as soon as your favorites are back in stock! 

Our 60-day guarantee is our way of saying, we know you’re going to love Proof undies - but, if for whatever reason you are unsatisfied or our products do not meet your expectations, you can return them within 60 days for a full no-questions asked refund!

*60 days from the time of receipt of order.

We do our best to make you happy. But, if for whatever reason you don't love your Proof, you can easily start a return here.

FAQs for Proof Underwear

Period Panties - Frequently Asked Questions