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Size guide

Thunderpants 90/10 organic cotton/spandex blend is super stretchy, soft, and sturdy. We bind the undies with the same material as we use for the body, so there’s no scratchy elastic that digs in. They are the ultimate comfy easy-fit undie.

The undie styles are designed to sit in the natural curves of the body and are cut to be full coverage: with plenty of fabric to cover your bum. Because our fabric is a bit thicker than you may be used too and has great retention and recovery, they may feel like they fit a bit tighter. 

See the size guides below to help you choose the right size. If you happen to fall between the measurements in the Undies, we usually recommend sizing up for most people. Our fabric is stretchy enough that a bigger size will often still fit, but won’t feel as tight. If you would rather feel snug in your clothes opt for the smaller size. For the other garments, Bralettes, Bike Shorts, Leggings, Camis, you may want to size down for a snugger fit. These garments will offer a little more secure and supportive in a smaller size. 

If you still have questions feel free to email us for guidance! info@thunderpantsusa.com 

 

  • Underwear / Swim Bottoms
    Dress Size (US) Waist (Inches) Hip (Inches
     X Small 0 23-25 31-33
    Small 2-4
    27-29
    35-37
    Medium 6-8
    31-33
    39-41
    Large 10-12
    35-37
    43-45
    X Large 14-16
    39-41
    47-49
    2X Large 18-20
    43-45
    51-53
    3X Large 22-24
    47-49
    55-57
  • Women's Hipster vs. Original vs. Sky Rise

    The three styles are cut the same through the butt and legs, but the Hipster has a shorter rise than the Original and Sky Rise. The Hipster goes to about the low hip (thus the name Hipster!), the Original is 2” higher and usually hits below the belly button, the Sky Rise is our high waisted version that will hit at your natural waist, tapering in at the top.

    The Hipster is more of a low rise style, the Original a higher rise - but not a high waist, and the Sky Rise a true high waisted undie! The Original is by far our more popular style and a little easier fit on most body types.

    hipster vs original vs sky rise fit thunderpants
  • Underwear Size Conversion
     Underwear Size 4 5 6 7 8 9 10
    Dress Size 2-4 4-6 8-10 12-14 14-16 16-18 18-20
    Hip Inches 34-35 36-37 38-39 40-41 42-43 44-45 46-47
  • Bralette/Camisole/Swim Tops

    The bralettes are great for everyday wear for those of you who don't love wearing underwire and restricting bras. They're made with the same Organic Cotton as the underwear which makes them durable, stretch enough to cover your cup size, and have a great snap back to give some support. There is an elastic band around the under bust to hold everything up and in place.

    If you fall in between sizes, don't worry! We would recommend going down in size if you want more support and a snugger fit, or going up in size if you would like less support and some extra breathing room.

    Bra Size Underbust (Inches)
    Small 32
    28-29
    Medium 34
    30-31
    Large 36
    32-33
    X Large 38
    34-35
    2X Large 40
    36-37
  • Leggings & Bike Shorts
    Dress Size (US) Waist (Inches) Hip (Inches
     X Small 0 23-25 31-33
    Small 2-4
    27-29
    35-37
    Medium 6-8
    31-33
    39-41
    Large 10-12
    35-37
    43-45
    X Large 14-16
    39-41
    47-49
    2X Large 18-20
    43-45
    51-53
    3X Large 22-24
    47-49
    55-57
  • Kids
    SIZE Age
    Unisex Small (Pre-school) 2-4 years
    Medium 5-7 years
    Large 8-10 years