How to Size Adult Diapers and Incontinence Underwear

Quick answer: To size adult diapers or incontinence underwear, measure around your waist at the belly button and around the widest part of your hips. Use the larger measurement and match it to the brand's size chart. If you're between sizes, choose the smaller size for briefs (tabs adjust) and check the brand's advice for underwear.

Medical Disclaimer: The information in this guide is intended for general informational purposes only and does not constitute medical advice. Product recommendations are based on common use cases and should not replace a consultation with a qualified healthcare professional. Always speak with your doctor, nurse, or continence specialist before starting, changing, or stopping any treatment or product regimen. If you experience pain, infection, skin breakdown, or any unusual symptoms, seek medical attention promptly. We do our best to keep this information accurate and up to date, but we can't guarantee that it is complete or error-free.

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How to measure

  1. Use a soft measuring tape.
  2. Waist: measure around your waist at the level of your belly button.
  3. Hips: measure around the widest part of your hips and buttocks.
  4. Keep the tape snug but not tight, and stand relaxed.
  5. Use the larger of the two numbers.

Why size matters more than absorbency

A product that's too big leaves gaps at the legs, where most leaks happen. A product that's too small can dig in, cause irritation, and tear at the tabs. Many leak problems are solved by switching to the right size, not a heavier product.

Signs your fit is wrong

Sign Likely problem
Leaks at the legs Too big, or leg gathers tucked under
Red marks or irritation Too small or too tight
Tabs overlap a lot Too big
Tabs barely reach Too small
Sagging when wet Too big, or needs higher absorbency

Sizes vary by brand

A medium in one brand may be a large in another. Always check the size chart on each product page before ordering.

Frequently asked questions

What if my waist and hips are different sizes?

Use the larger number.

Should I size up for more absorbency?

No. Bigger sizes don't add absorbency in the right place. Choose the right size and a higher absorbency level instead.

What size should I buy for someone else?

Measure them if you can. If not, check the size of products they already wear, and compare brand charts.

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