The Test

KLOON Boxer Briefs: My Honest Pre-Launch Wear Test

I recently received a pair of the much-anticipated KLOON boxer briefs as part of a pre-launch testing round. Here's the full, unedited account of six months of wear, twenty normal washes, and two I probably shouldn't have done.

I had been waiting to try them for a while, mainly because KLOON has taken a slightly different approach from most underwear brands. Rather than using ordinary cotton or a basic synthetic blend, the boxers are made from TENCEL™ Modal, a silky-soft, cellulose-based fabric produced by Lenzing in Austria using beechwood as its raw material.

I have worn modal underwear before, and modal has gradually become my preferred underwear fabric. It is generally softer and smoother than cotton, while also handling moisture better. Because of that, I was curious to find out whether KLOON would actually feel different from the modal boxers I had already tried, or whether the fabric story was mostly clever marketing.

I was also interested in the waistband. KLOON describes a milk-silk waistband, which was not something I could remember having tried before. Waistbands are often overlooked when people review underwear, but they make a significant difference. A waistband can feel excellent when new and then quickly become stiff, twisted, loose or uncomfortable after repeated washing.

To test the boxers properly, I used them through a longer range of everyday situations, including full office days, walking, workouts, ordinary daily activity and even a sauna session. I also washed them repeatedly. Most washes were done at the advertised 40°C, but I deliberately put them through a 90°C boil wash as a stress test several times, not how KLOON recommends caring for them, but I wanted to see how badly a much harsher wash than intended would affect the fabric, waistband and fit.

First impressions

The first thing I noticed when handling the KLOON boxers was the fabric. Many brands describe their underwear as soft, but softness can mean several different things. Some fabrics feel fluffy, while others feel slippery or heavily treated. KLOON feels smooth and silky without feeling artificial.

The material is also relatively light, but it does not feel thin or fragile. There is still a lot of structure for the boxers to maintain their shape. Somehow it's light and strong at the same time.

Some very soft underwear feels fantastic when you first put it on but gradually loses its form during the day. The fabric begins to bunch up, the legs move, and the pouch stops giving meaningful support. That was not my experience with KLOON. I have worn modal underwear from other brands, and it was already my favourite material before this test. Even so, the KLOON fabric feels noticeably better than the modal products I have previously owned.

95% TENCEL™ Modal, 5% spandex: the fabric this review kept coming back to.

Fit and sizing

Sizing was the biggest surprise of the test. I normally wear a size Large in boxer briefs and have done so across several different brands. My waist measures approximately 90 centimetres, so I initially expected the KLOON Large to be the obvious choice.

Instead, the Large felt slightly too big, not unwearable, but it did not provide the close, secure fit I expect from boxer briefs. The Medium, on the other hand, was an absolute perfect fit. That was unusual for me; I cannot remember needing a medium in another boxer brand during the last 15 years.

This is worth paying attention to when ordering: people who regularly sit between two sizes may be better served by choosing the smaller one. That said, sizing is individual, so I wouldn't claim everyone should automatically size down. It's simply something KLOON may want to clarify through a highly accurate size guide.

The 3D pouch

The three-dimensional pouch is one of the strongest parts of the design. A lot of underwear brands talk about anatomical support, but the result often feels like compression, especially after a couple of washes. KLOON provides support without packing everything tightly. There is actual room in the pouch, and the fabric follows the shape of the body instead of flattening it.

Another major benefit was the lack of fabric slipping into the groin. With many boxer briefs, the legs or centre seam gradually move inward, especially after sitting, walking or standing up repeatedly. The KLOON boxers sat remarkably well throughout the day, once I had the correct size, they stayed in place without squeezing my thighs. The best underwear is often the underwear you stop thinking about.

Long office days

Office use was one of the most relevant parts of the test for me. Sitting at a desk for eight or ten hours can be just as demanding on underwear as exercise: limited airflow, one position for long periods, heat and moisture building up. Cotton can become noticeably damp during these kinds of days and stay that way.

The KLOON fabric handled this much better. I wouldn't claim the boxers somehow prevent sweating (no underwear can do that), but the fabric appeared to move and release moisture more effectively than the traditional cotton underwear I've used. Odour was also less noticeable across my test period.

Workouts and movement

During workouts, the boxers continued to stay in place surprisingly well. The legs did not constantly roll upward, and the pouch provided enough support for ordinary gym activity without excessive pressure. For my use it worked especially well for both running and weight lifting. I had no issues with chafing, support or crouching, and I didn't have to repeatedly reposition anything, which is normally what bothers me most during exercise.

The sauna test

Wearing boxer briefs in a sauna wasn't a planned test (I forgot my towel), but it gave me an unplanned chance to see how the fabric behaves under high heat and moisture. It became warm and damp, as expected, but the fabric stayed soft rather than turning stiff or rough, didn't feel as heavy as soaked cotton, and kept its shape afterward. It reinforced my impression that the fabric, and the waistband, hold up better than conventional materials under real stress.

Washing at 40°C

Most washing was done at the recommended 40°C. After roughly 10–12 normal washes, there was little to no obvious change in the overall fit: the legs, pouch and waistband retained their shape, and the material still felt close to how it felt when new. That matters, because modal can occasionally develop a slightly worn or fuzzy surface over time in lower-quality fabrics. So far, KLOON has held up very well.

The 90°C stress test

I also washed the boxers at 90°C a couple of times, an intentional stress test, not a recommended method, and not something I'd suggest doing regularly since washing far above the care instructions can shorten a garment's life. I expected visible shrinkage, stiffness or waistband damage. Instead, the boxers came out with very little noticeable change: fit and softness held close to what they were before, with only a small amount of colour/logo fade. A couple of extreme washes isn't the same as doing it every week, but it suggested the construction can survive more than I expected.

The waistband

The milk-silk waistband was another strong point: extremely smooth, without the scratchy or rigid surface some elastic waistbands have, and it doesn't dig in when sitting. It stretches evenly and returns to shape without feeling overly tight, and it kept both its elasticity and softness through repeated washing. A waistband is usually the first part of a boxer to show age; so far, none of the usual issues (loosening, rippling, folding) have shown up here.

My one note is purely visual: the KLOON logo is currently woven into the waistband, and I think a cleaner printed logo might suit the understated design a little better. That's a matter of taste, not a performance issue.

No physical care label

KLOON has removed the traditional sewn-in washing label and instead prints the care information directly onto the fabric: a good call for comfort, since sewn labels are one of those small irritations that get more noticeable the longer you wear something. The trade-off: the printed care information began to fade after only a few washes. It doesn't affect the boxer itself, but it's worth KLOON improving the durability of the print, or offering the care instructions somewhere permanent: a QR code, the packaging, or the order confirmation.

Durability so far

At the time of writing, the boxers are still holding up extremely well after extended wear and repeated washing: no thinning fabric, intact seams, no shrinking, and a waistband that still performs like it did on day one. A truly complete durability verdict would need many months or more than a year of regular wear, so I can't make a definitive long-term claim. But nothing about the boxers so far suggests the softness came at the expense of durability.

"KLOON has created an unusually comfortable pair of boxer briefs, and the honest issues are minor next to that."

What I would improve

My main criticism is the sizing: a Medium fitting better than a Large at a 90-centimetre waist is unexpected based on my experience with other brands, and I'd like to see KLOON refine or explain their sizing more clearly. My second is the durability of the printed washing information. My third is purely cosmetic: I'd consider a sewn logo over the current woven waistband treatment. These are relatively small issues, and only the sizing had a meaningful effect on my initial experience.