The Super Absorbent. Super Comfortable. Super Safe. Super Sustainable. Super Loved Period Underwear.

This style runs true to size. Order your most standard size. 

You can see our size chart here.

Our Fabrics

Body: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

None, zero, nada, zilch. We are proud to be one of the few period underwear brands that do not use any toxins in our products because who wants chemicals near the most sensitive part of their body? Not us. Or you.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a Coral Reef: Hi! Thank you for using non disposable products. It may feel like a small gesture - but it’s not. I’m sick of getting tampons and pads getting caught up in my beautiful branches and you’re helping to keep that trash out of my home. Just one pair of Period means that 5 pads/9 tampons are never used or thrown away. Thank you! Next time you swim by me, stop and say hi. 

This style runs true to size. Order your most standard size. 

You can see our size chart here.

Our Fabrics

Body: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from an Octopus: Hi. I wanted to send you a personal message of gratitude for being conscious enough to stop using disposable products. Imagine me now, shaking your hand eight times. That’s what I’m doing. And sending you good energy with my two hearts. Tampons and pads take generations to biodegrade, cause endless pollution and they are frankly stupid inventions - and I should know what stupid is because I have eight brains. Be proud of yourself - you’re making a big change. 

This style fits like a true bike short. If you want a more relaxed fit, we recommend sizing up!

You can see our size chart here.

Our Fabrics

Body: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a used tampon: Hi, I’m a tampon that was last used in 1946 - only once - and I’m still languishing on a land fill. As you can imagine, I’ve had a lot of time to reflect. What was the point of me? Why did someone use me once for just a few hours and nearly a hundred years later, I’m still here? Why? This feels like a pretty stupid system to me. Please overthrow it! Please use non-disposable products so that no tampon ever has to feel this useless again. Thank you. 

This style fits like a true boxer brief, if you want a more relaxed fit, we recommend sizing up!

You can see our size chart here.

Our Fabrics

Body: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a frog: you’re doing it, you’re saving the world from waste, and more than that, embracing a new way of thinking when it comes to periods. I am in awe. Enjoy the boxer! 

This style is intended for postpartum use and is very supportive in the lower abdomen area. if you want a more relaxed fit, we recommend sizing up. 

You can see our size chart here.

Our Fabrics

Body: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a Coral Reef: Hi! Thank you for using non disposable products. It may feel like a small gesture - but it’s not. I’m sick of getting tampons and pads getting caught up in my beautiful branches and you’re helping to keep that trash out of my home. Just one pair of Period means that 5 pads/9 tampons are never used or thrown away. Thank you! Next time you swim by me, stop and say hi. 

This style runs true to size. Order your most standard size. 

You can see our size chart here.

You can see the length of the absorbent panel here.

Our Fabrics

Body: 95% Cotton with 5% Spandex Jersey

Absorbent Layer: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Medium Flow Period. underwear can hold up to 4 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a Star Fish: I wanted to tell you that on this rare instance, I’m not the star. You are. By wearing just one pair of Period, you’ve saved the world from 4 tampons that will take generations to decompose and let’s not get into pads. Thank you from the bottom of the ocean.

This style runs true to size. Order your most standard size. 

You can see our size chart here.

Our Fabrics

Main: PeriodTech™ 85% Nylon with 15% Spandex Knit

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a turtle: Oh hello. When you're my age (110 years old), you've seen a lot of stuff. I hope I live to see a world where there's no more non-disposable garbage in the ocean like tampons and pads. Sometimes I feel pretty down about the whole situation. Then, I hear about people like you who are shifting behaviors and making a difference and I get that warm feeling (unusual for turtles) where I just know everything is going to be ok.

This style runs true to size. Order your most standard size. 

You can see our size chart here.

Our Fabrics

Main: PeriodTech™ 85% Nylon with 15% Spandex Knit

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 10 tbls, or 8-10 tampons, worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a Cheetah: Hi! You know me. You know how much I love to run. Running is the best thing in the universe. The only that ruins it is when you run past a decomposing tampon or pad. Man, that sucks. There are some things you can't unsee and that's one of them. But not for much longer! With incredible people like you, we're going to end all this ridiculous waste and make my runs fantastic again. Kudos.

This style runs true to size. Order your most standard size. 

You can see our size chart here.

Our Fabrics

Main: PeriodTech™ 85% Nylon with 15% Spandex Knit

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 2 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a blade of grass: Hi! You might notice me. I am one of a trillion trillion blades of grass. But I notice you. With just one pair of Period underwear, you're saving the Earth from so much non-disposable junk. I have some blade of grass friends who live near landfills and let me tell you, slow decomposing tampons and pads are not pretty. Next time you see a breeze going through a field of grass, know that it's us waving hello and thank you at you.

This style runs true to size. Order your most standard size. 

You can see our size chart here.

You can see the length of the absorbent panel here.

Our Fabrics

Main: 90% Polyester 10% Spandex

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Proof Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Medium Flow Period. underwear can hold up to 4 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a Star Fish: I wanted to tell you that on this rare instance, I’m not the star. You are. By wearing just one pair of Period, you’ve saved the world from 4 tampons that will take generations to decompose and let’s not get into pads. Thank you from the bottom of the ocean.

This style runs true to size. Order your most standard size. 

You can see our size chart here.

You can see the length of the absorbent panel here.

Our Fabrics

Main: 90% Polyester 10% Spandex

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Medium Flow Period. underwear can hold up to 4 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from an Oak Tree: Hellooo. I’m a 100 year old oak tree. I live near a landfill and 80 years ago, I saw a tampon get thrown away. Guess what? It’s still there! Still decomposing! I can’t believe it. All the pads and tampons that people have thrown away are all there. And it’s so gross! I used to look out at fields and meadows and woodland. And now I just see decomposing bad products that will taken another hundred years to degrade. I have to confess, I started to lose a little faith in humans. Then you came along. Just by wearing one pair of Period just once, you’ve stopped 2 pads or 4 tampons from being in my eye line. Thank you!

This style is intended for teenagers or petite adults and runs true to size. 

Teens should order their most standard size. 

A petite women's extra small can comfortably fit in a teen medium.

A petite women's small can comfortably fit in a teen large.

You can see our size chart here.

Our Fabrics

Body: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Proof Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Personal message from the entire ecosystem: thank you for using non-disposable products, it’s this kind of thinking and your generation that’s going to help save The Planet. Thank goodness, you came along.

This style runs true to size. Order your most standard size. 

It’s normal for the garment to fit snug when dry. It will relax and grow about half a size when wet.

A petite women's extra small can comfortably fit in a teen medium.

A petite women's small can comfortably fit in a teen large.

You can see our size chart here.

You can see the length of the absorbent panel here.

Our Fabrics

Main: 80% Recycled Nylon, 20% Spandex

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Give your Period. a quick rinse after leaving the water.

Hand wash cold with a mild detergent. 

 Hang dry. Do not bleach or dry clean.

Our crotch liner is non toxic, but can leave a residue when taken off.  Use the following care instructions for the first wash:

1. Remove liner and dispose. It’s compostable!  

2. Throw in the wash with hot water. Use a mesh laundry bag if possible.

3. While wet, remove any additional residue before drying.

We know it’s a few extra steps, but one less piece of plastic in the ocean is totally worth it.

Each pair of Period. swimwear can hold up to 2 tampons worth of blood.

How long will one pair of Period. swimwear last?

You can swim as long as you want. Period blood really doesn’t come out in the water because of the water pressure. But you do flow on the beach, by the pool, the lake etc… That’s what Period Swim absorbs. One pair can hold up two tampons worth of blood.

Have more questions?

Check out our Swim FAQ's here (scroll to bottom of page).

Message from an Oak Tree: Hellooo. I’m a 100 year old oak tree. I live near a landfill and 80 years ago, I saw a tampon get thrown away. Guess what? It’s still there! Still decomposing! I can’t believe it. All the pads and tampons that people have thrown away are all there. And it’s so gross! I used to look out at fields and meadows and woodland. And now I just see decomposing bad products that will taken another hundred years to degrade. I have to confess, I started to lose a little faith in humans. Then you came along. Just by wearing one pair of Period just once, you’ve stopped 2 pads or 4 tampons from being in my eye line. Thank you!

This style runs true to size. Please order your most standard size.

You can see our size chart here.

Our Fabrics

Body: 94% Polyester Brushed Microfiber with 6% Spandex Jersey

Lining: 95% organic cotton, 5% spandex

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Personal message from soil: I know it’s highly unusual to get a message from soil but in this case, I just had to say thank you. Just by using one pair of Period underwear, you’re saving the natural world from 9 tampons or 4 pads being thrown away and (because they don’t biodegrade) polluting the Earth for generations. From me and all my microbes - thank you. 

This style is intended for teenagers or petite adults and runs true to size. 

Teens should order their most standard size. 

A petite women's extra small can comfortably fit in a teen medium.

A petite women's small can comfortably fit in a teen large.

You can see our size chart here.

Our Fabrics

Body: 94% Nylon Brushed Microfiber with 6% Spandex Jersey

Lining: 95% organic cotton, 5% spandex

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from an Oak Tree: Hellooo. I’m a 100 year old oak tree. I live near a landfill and 80 years ago, I saw a tampon get thrown away. Guess what? It’s still there! Still decomposing! I can’t believe it. All the pads and tampons that people have thrown away are all there. And it’s so gross! I used to look out at fields and meadows and woodland. And now I just see decomposing bad products that will taken another hundred years to degrade. I have to confess, I started to lose a little faith in humans. Then you came along. Just by wearing one pair of Period just once, you’ve stopped 2 pads or 4 tampons from being in my eye line. Thank you!

This bag fits one pair of most Period. Underwear. 

Bag Dimensions 

6.75" (Height) x 8.75" (Length) x .75" (Width)

Shell: 100% Polyester

Lining: 100% EVA

Spot clean with a damp cloth only.

Do not wash. 

Do not dry.

Do not iron or steam. 

Do not bleach.

Do not dry clean.

This bag is lined with a waterproof material that keeps the rest of your bag safe from used products. 

Message from a turtle: Oh hello. When you're my age (110 years old), you've seen a lot of stuff. I hope I live to see a world where there's no more non-disposable garbage in the ocean like tampons and pads. Sometimes I feel pretty down about the whole situation. Then, I hear about people like you who are shifting behaviors and making a difference and I get that warm feeling (unusual for turtles) where I just know everything is going to be ok.

This style runs true to size. Order your most standard size. 

You can see our size chart here.

You can see the length of the absorbent panel here.

Our Fabrics

Main: 90% Polyester 10% Spandex

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Light Absorbency Period. underwear can hold up to 2 tampons worth of blood.

How long will one pair of Light Absorbency Period. last?

Everybody periods differently so it’s tough to be exact. Our light absorbency collection is for those lighter days - so after the big flow. Sometimes that easing off can start around day 3, or not even until 4 or 5. Or maybe, it starts for you on day 2. These are the days the lighter absorbency models are made for. Again, everybody Periods differently, so you need to take one cycle to figure out exactly when to pop on the lighter absorbency model and if you need to change twice a day, or not at all. Spend a day finding that limit. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the light absorbency underwear will last for you.

A personal message from a wild horse: Hi, I want to thank you for not using disposable products and for being wild and adventurous enough to try out a non-disposable thong. As a wild horse, you might not think I have anything to do with periods, but we’re living in an ecosystem where everything is connected, and the amount of waste and pollution out there affects all of us. You using sustainable products might not feel like a big deal, but because of that connection, it is. Thank you!

This style is intended for teenagers or petite adults and runs true to size. 

Teens should order their most standard size. 

A petite women's extra small can comfortably fit in a teen medium.

A petite women's small can comfortably fit in a teen large.

You can see our size chart here.

Our Fabrics

Main: PeriodTech™ 85% Nylon with 15% Spandex Knit

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from a Cheetah: Hi! You know me. You know how much I love to run. Running is the best thing in the universe. The only that ruins it is when you run past a decomposing tampon or pad. Man, that sucks. There are some things you can't unsee and that's one of them. But not for much longer! With incredible people like you, we're going to end all this ridiculous waste and make my runs fantastic again. Kudos.