How to Choose the Right Swim Trunk Inseam Length

So you've found a swim trunk print you love but now you're stuck choosing between a 4 inch, 5 inch, 7 inch... and wondering what on earth the difference actually feels like on. Sound familiar?

Inseam length is probably the most important fit decision you'll make when buying swim trunks, and yet most guys just grab whatever looks good in the photo without thinking about it. The result? Trunks that feel too long, too short, or just a little off.

This guide will help you figure out exactly which length is right for you, your body type, and how you actually plan to use them.

What Is Inseam Length in Swim Trunks?

The inseam is the measurement from the crotch seam down to the bottom hem of the trunk. The shorter the inseam, the higher the hem sits on your thigh. The longer the inseam, the closer it gets to your knee.

Simple enough, right? Here's how the different lengths actually look and feel.

The Complete Guide to Swim Trunk Inseam Lengths

4 Inch Inseam: Bold and Minimal

This is the shortest option and it's not for everyone. A 4 inch inseam sits high on the thigh and gives a very retro, European-inspired look. Think of it as the swim trunk equivalent of short shorts.

Best for:

• Guys who want maximum tan lines (or none at all)
• A retro or fashion-forward look
• Shorter guys who find longer trunks overwhelming on their frame
• Pool days and beach lounging

Not ideal for surfing or active water sports where you need more coverage and freedom of movement.

At Bermies these are the Short and Short Liner styles.

5 Inch Inseam: The Sweet Spot

The 5 inch inseam is by far the most popular length and there's a good reason for that. It sits just above mid-thigh, giving you a clean, modern look that's neither too short nor too long. It works on almost every body type and almost every occasion.

Best for:

• Most guys, most occasions
• Beach, pool, vacation, travel
• A versatile trunk that works as a casual short too
• Guys who want to look put-together without trying too hard

This is the Classic and Classic Liner at Bermies, and our best selling style.

6 Inch Inseam: Sleek and Versatile

The 6 inch sits between classic and traditional. It gives a bit more coverage than the 5 inch while still keeping a modern, tailored look. A great middle ground for guys who want something slightly longer but not a traditional boardshort length.

Best for:

• Guys who like a slightly more covered look
• Versatile wear from water to street
• A slim, tailored fit that works for casual occasions too

At Bermies this is the Tailored style, which also comes with a built-in compression liner and a phone pocket.

7 Inch Inseam: The Traditional Length

The 7 inch is the classic American swim trunk length. It falls just above the knee on most guys and gives a more relaxed, traditional fit. If you grew up wearing board shorts in the 90s, this is probably the length you're most comfortable with.

Best for:

• Guys who prefer more coverage
• A relaxed, traditional fit
• Taller guys who find shorter trunks look too minimal
• Casual beach and pool days

At Bermies these are the Long and Long Liner styles.

8 Inch Inseam: The Boardshort

The 8 inch is the longest option and the closest to a traditional boardshort. It typically hits at or just above the knee and is designed for active water use, especially surfing.

Best for:

• Surfing and active water sports
• Guys who want maximum coverage and a boardshort feel
• Taller guys
• A more athletic, performance-oriented look

At Bermies this is the Boardshort Liner, a hybrid boardshort with built-in compression liner.

Quick Reference Guide

 

How to Choose Based on What You're Doing

As a general rule:

• Under 5'8": shorter inseams (4" or 5") tend to look more proportional
• 5'8" to 6'1": the 5" or 6" hit the sweet spot on most frames
• Over 6'1": a 6", 7" or even 8" can look more balanced and proportional

That said, there are no hard rules here. Wear what you feel good in.

HOW TO CHOOSE BASED ON WHAT YOU'RE DOING

• Surfing or active water sports: go with 8" boardshort
• Beach and pool vacation: 5" or 6" is perfect
• Traveling light and want one trunk that does everything: 5" Classic Liner or 6" Tailored
• Gym to beach days: 4" or 5" Short Liner for maximum mobility
• Just chilling at the pool: honestly any length works, pick what you like

THE BOTTOM LINE

If you have no idea where to start, start with a 5 inch inseam. It's the most versatile, the most flattering on most body types, and the most wearable across different occasions. You can always add a shorter or longer pair to the rotation once you know what you like.

Still not sure? Check out the full Bermies lineup and use the inseam filter to narrow it down. And if you want the added comfort of a built-in liner, all our styles come in a compression liner version too.