Between Two Underwear Sizes? How to Decide

If your waist measurement falls between two Gigo underwear sizes or directly on a shared boundary, start with the larger size. That is the current recommendation in the official Gigo Size Guide.

You do not need a complicated formula. Measure your waist, compare it with the Gigo Size Guide and use the larger size as the recommended starting point when two ranges meet.

What Does “Between Two Sizes” Mean?

Gigo sizes are ranges, so some measurements appear at the end of one size and the beginning of the next.

For example, 31 inches appears at the boundary between S and M. Under the current Gigo recommendation, M is the starting point at that shared boundary.

The same principle applies at the other shared boundaries in the chart.

Measure Your Body, Not Your Underwear

Use a soft measuring tape around the area where you normally wear the waistband of your underwear, usually just above the hip bones.

• Stand naturally.
• Keep the tape level.
• Do not pull it tight.
• Use that body measurement in the Gigo chart.

Why Start With the Larger Size?

The goal is comfort and normal freedom of movement while preserving the support and shape intended by the garment.

Choosing the larger starting size does not mean the underwear should become loose. It simply avoids forcing the entire garment smaller when your body measurement sits on the limit between two ranges.

Do Not Choose the Smaller Size Just for a Tighter Look

If you want a closer or more revealing silhouette, choose the cut that gives you that look rather than automatically buying a smaller size.

A brief, trunk, jockstrap or G-string creates its own amount of coverage and body definition.

Start with the recommended size, then choose the silhouette you prefer.

Size and Cut Are Not the Same Thing

The same waist measurement can work across different Gigo lower-body styles, while the garments themselves feel different because of their construction.

A brief leaves the thigh open. A trunk adds a short leg. A jockstrap uses an open back and straps.

Those differences do not mean you need a new sizing system for every cut.

How to Confirm Your Choice

When you try the garment on, keep the check simple:

• The waistband should stay comfortably in place.
• The front should feel secure without uncomfortable pressure.
• You should be able to sit, walk and move normally.

If those three things work, there is no reason to turn sizing into a bigger problem.

What If One Area Feels Different?

Different cuts naturally feel different around the thigh, back or pouch.

If your waist feels right but you prefer a different amount of coverage or openness, try another cut before assuming the size itself is wrong.

Underwear is not supposed to feel identical across every silhouette.

Do Not Use Height or Another Brand’s Letter Size

Height does not determine your Gigo underwear size, and a medium in another brand may use a different waist range.

Use your current waist measurement and the current Gigo chart instead.

The Simple Rule

Measure your waist. Check the Gigo chart. If you are between two sizes or on a shared boundary, start with the larger size.

Then choose the style you like and move on to the more interesting part: the cut, color and design.

For the full explanation of body measurements and size ranges, read how to measure men’s underwear size.

View the official Gigo Size Guide or browse men’s underwear.