New Colors - Surf and Coral!

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

You can see our size chart here.

Our Fabrics

Main: PeriodTech™ 95% Nylon with 5% Spandex Knit

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 88% Polyester with 12% Nylon 

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse any fresh blood off in the sink or the shower.

Hang to dry then add to your laundry pile. 

Machine wash warm, no bleach.

Tumble dry low. Do not dry clean or iron. 

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

Check out our absorbency test video 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™ 95% Nylon with 5% Spandex Knit

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 88% Polyester with 12% Nylon 

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse any fresh blood off in the sink or the shower.

Hang to dry then add to your laundry pile. 

Machine wash warm, no bleach.

Tumble dry low. Do not dry clean or iron. 

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.

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™ 95% Nylon with 5% Spandex Knit

Lining: 95% Organic Cotton with 5% Spandex Jersey

Absorbent Layer: 88% Polyester with 12% Nylon 

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse any fresh blood off in the sink or the shower.

Hang to dry then add to your laundry pile. 

Machine wash warm, no bleach.

Tumble dry low. Do not dry clean or iron. 

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

Check out our absorbency test video 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 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.