The Trunk Is the Sweet Spot
Shorter than a boxer brief, more covered than a brief, and quietly the right answer for a lot of men who have never tried one. The case for the trunk.
Briefs, Boxers, Boxer Briefs or Trunks: How to Choose
The five types of men's underwear, and a way to choose between them based on your trousers, your thighs and your day rather than a flatmate's opinion.
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Most men choose their underwear style once, at about nineteen, on the basis of something a flatmate said, and then never revisit the decision for forty years. Cars get replaced. Opinions on music get quietly abandoned. The underwear drawer is carried through life unexamined, like a surname. Some of us would quite like a word with that nineteen year old A Letter to My Nineteen Year Old Self, Who Wore Boxers.
This is the article that examines it. No style wins here. Different bodies, different trousers and different days want different things, and the sensible end point is a drawer with two or three styles in it rather than a doctrine.
The five things you are choosing between
The brief. Cut high on the leg, no leg at all really, supportive pouch, sits on or just below the hip bone. The oldest engineered design in the drawer, patented in 1934, and still the standard across most of Asia, southern Europe and Latin America Where the World Wears Briefs: An Atlas. Least fabric, least heat, least to go wrong.
The trunk. A brief with a short, square leg, usually two to four centimetres of thigh. Squarer through the seat than a brief, shorter than a boxer brief. The compromise nobody talks about and a lot of men would be happier in The Trunk Is the Sweet Spot.
The boxer brief. The same supportive construction with the leg carried down the thigh, somewhere between mid-thigh and just above the knee. The most-worn style in the West and, on the numbers, the most-worn style full stop in several large markets The Boxer Brief Won, and It Deserved To.
The loose boxer. Woven or knitted, cut generously, no meaningful support, an open or buttoned fly. Sleepwear that got promoted. Genuinely lovely in the right circumstances and genuinely useless in the wrong ones In Praise of the Loose Boxer.
The jockstrap. A waistband, a pouch, two leg straps and nothing across the seat. Built for one job, still the best thing in existence at that job The Jockstrap Never Left the Locker Room.
Start with your trousers
This is the filter that eliminates the most options fastest, and almost nobody applies it.
Slim or tailored trousers show everything underneath them. Anything with a hem that stops mid-thigh puts a horizontal line across the leg of the trouser, and in a light-coloured summer trouser that line is visible from across a room. Briefs and trunks sit above the point where the trouser starts to skim, so they leave nothing to see. Boxer briefs work if they are long enough to sit below the widest part of the thigh and cut close enough not to bunch. Loose boxers under slim trousers are a losing battle and always have been.
Loose or heavier trousers, workwear, jeans with room in them, suit trousers with a proper break: everything works. Choose on comfort instead.
Shorts in summer are their own problem, since a boxer brief hem and a short hem land within a few centimetres of each other and the layering shows. Briefs or trunks solve it.
Then your thighs
Skin rubbing on skin is the single most underrated variable in this entire subject, and it is the one honest advantage the longer leg has.
If your thighs touch when you walk, and a great many men's do, at least in summer, at least after a long day, a leg that stays put is worth having. That is the whole case for the boxer brief in one sentence, and it is a good case. Cyclists and runners worked it out decades ago.
If they do not touch, or only in the sort of heat you get a few weeks a year, the extra fabric is doing nothing except making you warmer and giving itself an opportunity to ride up. Briefs and trunks get you a cooler, lighter garment with less to manage.
The test is not complicated. Walk five kilometres in something short-legged on a warm day and see what happens.
Then what you do all day
Sitting at a desk, sitting in a car, sitting in a meeting: support matters more than coverage, and heat matters more than either. Briefs and trunks in something breathable modal brief.
On your feet, on a site, up and down a ladder: you want something that does not shift and does not need adjusting in front of anyone. Boxer briefs or a supportive brief in a technical fabric The Working Man's Brief: Underwear for the Site, the Van and the Ten-Hour Shift.
Running, lifting, cycling, anything with impact: closest fit wins, and the loose boxer is simply not a candidate Right Support, Right Sport: What to Wear for What You Do.
Long-haul travel, humid climates, a rucksack and one wash basin: least fabric dries fastest and packs smallest Travel Light: The One-Bag Case for Briefs.
At home on a Sunday with nothing to do and nowhere to be: loose boxers, obviously, and anybody who tells you otherwise is not being honest about Sundays.
The fabric question, briefly
Style decides the shape. Fabric decides whether you enjoy wearing it.
Cotton is comfortable, cheap and slow to dry, which makes it excellent for a normal day and poor for a hot one or a hard one. Modal and micro-modal are softer, drape better and cost more. Merino is the outlier that regulates temperature in both directions and resists smell for days, which is why it dominates hiking and travel. Synthetics wick fastest and hold odour worst. There is a longer version of all this if you want it The Sweat Article: Moisture-Wicking Fabrics, Explained Properly.
A cheap boxer brief in a good fabric beats an expensive one in a bad one, every time.
A drawer, not a doctrine
The end point most men land on, once they actually try the options rather than inheriting one, looks something like this. A working majority in whichever close-fitting style suits their body and their trousers. A few briefs for hot days, tailoring and travelling light. A couple of pairs of loose boxers for evenings and weekends. A jockstrap in the gym bag if sport is a real part of the week.
That is not a compromise. That is just owning the right tool more than once, which nobody finds odd when it applies to shoes.
If you are only going to change one thing this year, make it fit rather than style. A boxer brief a size too small rides up. A brief a size too big does nothing at all. Most men are wearing the wrong size in the right style and blaming the style.
Questions people ask
What is the difference between a trunk and a boxer brief?
Leg length, mostly. A trunk has a short square leg of roughly two to four centimetres and stops well above where the thigh widens. A boxer brief carries the leg down the thigh, typically twelve to twenty centimetres. A trunk is also usually cut squarer through the seat. If a boxer brief feels like too much fabric and a brief feels like too little, the trunk is the answer sitting between them.
Which style is best for a suit?
Anything that does not put a horizontal line across the trouser leg. Briefs and trunks are the safest, and a boxer brief works if it is long and close enough to sit flat below the widest part of the thigh. Skin-tone rather than white matters more than people expect under a pale summer suit Briefs for the Office: The Tailoring Argument.
Do loose boxers cause any real problems?
Only in the sense that any garment is bad at a job it was not built for. They provide no support, so they are poor for sport, poor for long walks and poor under slim trousers. For sitting around, sleeping and hot still evenings they are excellent. The mistake is treating them as an all-purpose default rather than one option among several.
How often should underwear be replaced?
When the waistband stops gripping or the fabric goes thin and grey, whichever comes first, which for a decent pair worn weekly is usually somewhere between two and four years. A stretched waistband is the tell, because that is the part doing most of the work and the part that fails first Buy It Once: The Durability Guide to Briefs That Last Years.