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Underwear Size Chart and Fit Guide

Underwear Size Chart and Fit Guide

Underwear Size Chart and Fit Guide

Knowing your underwear size isn’t always easy and can lead to many purchases that quickly end up in the trash. From fit preferences to appearance, sometimes you really don’t know what looks and feels right until you try them on. If you’re on the brink of giving up and going commando we have the solution for you.

To help you find your dream fit every time, we created an underwear size chart with measuring tips and a fit guide to help you know your specific measurements no matter what brand or style.

How to Use the Underwear Size Chart

The first step in using our underwear size chart is knowing your body’s measurements. Knowing your body’s measurements is important for finding your perfect fit since sizes can vary.

Men's underwear sizes and fits are very different so we’ve broken down measurement tips to help you find the perfect size based on your body type and preferences.

Men’s Underwear Size Guide: How to Measure

When it comes to measuring for men’s underwear size there are a few differences than for women. Since men’s underwear hits at the waist level, there’s no need to measure at the hips.


  1. Measure Waist Size

How do I measure my waist? Start at the top of your hip bone, then bring the tape measure all the way around your body, just above your belly button. Make sure it's not too tight and that your measure is level all the way around your body. Take a deep breath to ensure your measurement will fit comfortably.

  1. Find Your Underwear Size

If there's one thing on your body that should fit you like a glove, it's your underwear. Use our men’s underwear size chart below to locate your proper underwear size.

What if I’m Between Sizes?

A smaller size is best if you wear slimmer, more tailored shirts or pants. If you prefer a looser fit, size up.

Men's Underwear Size Chart

Tani USA uses letter sizing for our underwear.











How to Know If You Have The Right Underwear Size

By obsessing over every detail in our fabric, fit, and function, we have reinvented men's and women’s underwear to overcome the uncomfortable. That being said, it’s important to know how your underwear is supposed to fit and feel on your body.

Use our fit guides below to know how your underwear should fit properly.

Men’s Underwear Sizes: Fit Guide

For men’s underwear, fabric, cut, and fit can all impact the way a specific underwear size can look and feel. However, there are tell-tale signs whether undies fit or not.

  1. Waistband: The waistband should lay snug but not tight on your waistline or leave any red marks. If the waistband cuts your body at all then you should go up a size.
  2. Back/Butt: Fabric and fit should feel snug around your butt but not tuck or ride up. The fit should also not sag or else you should go down a size.
  3. Legs: Edges should fit loosely around your legs and should not ride up.
  4. Crotch: For optimal comfort, the fabric should fit close to the skin without being constricting or binding.


Men’s Underwear Sizes: Fit by Style + Type

From boxer briefs to trunks, all men's underwear styles offer differences in fit. Explore our fit by style and type guide below.

  1. Boxer Brief: Provides the fullest amount of coverage and should lay snug on your body.
  2. Relaxed Fit Boxer: Lays looser against the body for a more airy fit.
  3. Trunk: These boxers hit right at mid-thigh, creating a modern yet classy look for everyday wear.
  4. Brief: Offer minimal coverage while giving the most support.


Underwear Size Chart: FAQs

How do you determine underwear size?

All you need is a soft tape measure! Bend to the sides to reveal the natural crease in your waistline. Wrap the tape measure around your waist where you typically wear your pants.

This number, in inches, will give you your underwear size. For a more detailed breakdown, refer to our chart and step-by-step guide above.

What size underwear do I need?

After taking your measurements, refer to our men’s and women’s underwear size chart.


Should you size up in underwear?

If your underwear squeezes your waist, your skin bulges or you get constant wedgies then you should probably size up. Also, smaller size is best if you wear slimmer, more tailored shirts or pants. If you prefer a looser fit, size up.

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