F

Is Knix PFAS-free?

Across 19 graded products, Knix averages F (41/100). On disclosure, the brand says nothing publicly about PFAS. 2 of its products grade C or better. Grades are model-based estimates, not lab results.

Worth buying from Knix C or better, safest first

Teen Super Leakproof Reusable Snap Pads

Knix

Teen Super Leakproof Reusable Snap Pads

organic cotton/synthetic blend with waterproof backing

A
A
PFASAll
A · Very low PFAS2 flags

Lower-concern period pad; brand actively avoids PFAS in waterproof layer and provides third-party verification.

MADE SAFE Certified

Lab test found no PFAS

Knix Essential No-Show Bikini 5-Pack

Knix

Essential No-Show Bikini 5-Pack

Cotton-blend gusseted underwear; moisture-wicking fabric (likely polyester blend)

C
F
PFASAll
C · Moderate4 flags

Lower concern period underwear, but Knix has not publicly disclosed PFAS testing or commitment.

Risky category by default

Graded and flagged D and F, we’d swap these

Knix Momenta Racerback Sports Bra

Knix

Momenta Racerback Sports Bra

Nylon/spandex blend fabric (no reported specialty coating)

D
D · Elevated

Lower-concern sports bra; standard textile, but Knix has not disclosed PFAS stance.

Risky category by default

Knix Intimates & Sleepwear Catalyst Sports Bra Knix

Knix

Intimates & Sleepwear Catalyst Sports Bra Knix

Nylon, spandex, polyester blend (no water-repellent or stain-resistant treatment disclosed)

D
D · Elevated

Lower concern, basic athletic textile blend with no waterproofing or stain treatment disclosed, but verify final garment details.

Risky category by default

Knix Catalyst Front Zip Sports Bra

Knix

Catalyst Front Zip Sports Bra

nylon, spandex, elastane blend

D
D · Elevated

Lower concern; typical athletic blend with no known PFAS triggers, but brand offers no transparency.

Risky category by default

Knix Revolution Busty Bra

Knix

Revolution Busty Bra

Fabric blend (likely nylon, elastane, cotton base)

D
D · Elevated

Lower concern; no water-repellent claims, but brand transparency on PFAS is absent.

Risky category by default

Knix Intimates & Sleepwear Knix Revolution Adjustable Pullover Bra

Knix

Intimates & Sleepwear Knix Revolution Adjustable Pullover Bra

nylon, elastane, polyester blend with no disclosed coating

D
D · Elevated

Lower-concern basics; no PFAS red flags, but brand discloses nothing about chemical treatments.

Risky category by default

Knix SuperPlus Leakproof No- Show High Rise Underwear

Knix

SuperPlus Leakproof No- Show High Rise Underwear

Cotton/synthetic blend with proprietary waterproof/leak-resistant coating (unspecified)

F
F · High PFAS

Skip until Knix discloses coating chemistry or pursues third-party PFAS verification.

Waterproof or stain-proof treatment

Knix Women's Super Leakproof Dream Boxers

Knix

Women's Super Leakproof Dream Boxers

Fabric with waterproof/leak-resistant coating (unspecified chemistry)

F
F · High PFAS

Skip until Knix discloses coating chemistry or provides third-party testing.

Waterproof or stain-proof treatment

Knix Medium-Flow Leakproof Period Underwear

Knix

Medium-Flow Leakproof Period Underwear

Organic cotton/viscose with proprietary waterproof coating (unspecified)

F
F · High PFAS

Waterproof period underwear with no disclosed coating ingredients, higher uncertainty on PFAS risk.

Waterproof or stain-proof treatment

Knix Period Underwear Teen Leakproof UltraThin No-Show Bikini 3-Pack

Knix

Period Underwear Teen Leakproof UltraThin No-Show Bikini 3-Pack

Fabric + undisclosed waterproof/leakproof coating

F
F · High PFAS

Skip until Knix discloses coating chemistry or provides third-party testing.

Waterproof or stain-proof treatment

KT by Knix Super Leakproof Reusable Snap Pads

Knix

KT by Knix Super Leakproof Reusable Snap Pads

Reusable fabric with waterproofing layer; composition unspecified

F
F · High PFAS

Skip until waterproofing chemistry is disclosed, reusable pads typically need water-repellent coating treatment, often PFAS-based.

Waterproof or stain-proof treatment

Knix Heavy Flow & Bladder Leak Protection Boybrief

Knix

Heavy Flow & Bladder Leak Protection Boybrief

Absorbent core with waterproof backing (material unspecified by brand)

F
F · High PFAS

Skip until brand discloses waterproof coating chemistry, period-care products with moisture barriers often use PFAS-based water-repellent coating treatments.

Waterproof or stain-proof treatment

Knix Super Leakproof Cotton Boybrief

Knix

Super Leakproof Cotton Boybrief

Cotton with undisclosed waterproof/leakproof coating

F
F · High PFAS

Skip until Knix clarifies coating chemistry, waterproof menstrual underwear frequently uses PFAS-based water-repellent coating treatments.

Waterproof or stain-proof treatment

Knix Essential No-Show High Rise 5-Pack

Knix

Essential No-Show High Rise 5-Pack

Synthetic blend with moisture-wicking/waterproofing treatment

F
F · High PFAS

Skip until brand discloses waterproofing chemistry; period-care products with water-repellent coating treatments warrant PFAS clarification.

Waterproof or stain-proof treatment

Knix Heavy Flow & Bladder Leak Protection Bikini

Knix

Heavy Flow & Bladder Leak Protection Bikini

absorbent fabric blend + waterproof backing layer (unspecified)

F
F · High PFAS

Skip until Knix discloses waterproof treatment chemistry, period underwear's wetness barrier is a classic PFAS red flag.

Waterproof or stain-proof treatment

Knix Longevity Sports Bra

Knix

Longevity Sports Bra

Nylon blend with moisture-wicking treatment (water-repellent coating finish likely)

F
F · High PFAS

Skip until brand discloses PFAS status, sports bra's water-resistant finish is a PFAS red flag.

Waterproof or stain-proof treatment

Knix Catalyst Sports Bra

Knix

Catalyst Sports Bra

Nylon/polyester blend with moisture-wicking treatment

F
F · High PFAS

Skip until Knix clarifies waterproof treatment chemistry.

Waterproof or stain-proof treatment

Knix Engage Medium Impact Sports Bra

Knix

Engage Medium Impact Sports Bra

Nylon/polyester blend with undisclosed water-resistant treatment

F
F · High PFAS

Moderate concern, sports bra likely has water-repellent coating finish, but Knix discloses nothing about PFAS use or alternatives.

Waterproof or stain-proof treatment

Every grade uses the same public rubric. How grades work →