Measure your natural waist with a soft tape, then match that number with to SLY Collective’s size chart to pick your fit. If your waist falls between two sizes on the anatomical hammock pouch range, size up for a looser pouch with more room, or size down for firmer support. That’s the whole rule.
Everything else in this guide exists to help you get that waist number right and choose confidently when you’re sitting between sizes.
- Measure at your natural waistline, not your hip or your jeans size.
- Match the centimetre figure on to SLY Collective’s chart rather than guessing from another brand’s Medium or Large.
- Between sizes? Size up for room and airflow, size down for a firmer hold.
Pro Tip: Keep your tape measure snug but not tight. If you can slide a finger under it comfortably, that’s your natural waist reading.
How do I measure for SLY Collective’s size chart?
Grab a soft fabric tape measure and a mirror. Do this in your underwear or light clothing so nothing bulks out the reading.
- Find your natural waist. This sits roughly where your trousers rest when you’re not pulling them up, usually just above your hip bones and below your belly button. It’s not the widest point of your stomach, and it’s not your hip measurement.
- Wrap the tape around, level all the way as you check it front and back in the mirror. A tape that dips at the back gives you a false low reading.
- Stand naturally. Don’t suck in, don’t puff out. Breathe out normally and read the tape where it sits.
- Check your hips too if you carry more weight through the seat or thighs. For fuller builds, the hip measurement can push you up a size even when the waist number alone would suggest smaller, because the pouch and leg panels need room to move without pulling.
- Record the number to the nearest half centimetre. SLY Collective’s chart works in whole and half centimetre increments, so round to the nearest 0.5 cm rather than rounding up or down to the nearest whole number.
- Convert to inches only if you need to double check against an old pair. Divide centimetres by 2.54, or just use the inches column already printed alongside the cm figures.
The men’s underwear size chart on the SLY Collective site lists both cm and inches, plus the exact measuring method the brand designed the chart around, so cross checking is straightforward.
This isn’t a one minute job you rush before checkout. A measurement taken over a jumper, or with the tape twisted, throws the whole exercise out by two or three centimetres, which is often the gap between one size and the next.
Reading SLY Collective’s size chart correctly
SLY Collective’s chart runs on waist measurement in centimetres as the primary column, with inches alongside for reference, and standard size labels (S, M, L, XL and so on) mapped against each band. Centimetres are the more precise unit because inch increments round more coarsely, so lean on the cm figure when you’re near a boundary.
A few worked examples show how this plays out:
- A 76 cm waist converts to roughly 29.9 inches, which typically sits in the Small to Medium range depending on how close it falls to the chart’s exact cutoff.
- An 80 cm waist converts to about 31.5 inches, generally landing in Medium territory.
- An 88 cm waist converts to roughly 34.6 inches, which usually points to a Large.
Always check these against the live figures on the SLY Collective sizing page, since band cutoffs can shift slightly between product lines.
What changes between sizes isn’t just the waistband. Each size band adjusts the depth and width of the anatomical hammock pouch and the length of the leg panel. A Small built for a narrower waist has a tighter, more compact pouch shape; a Large gives more forward and downward space, which matters if you want the pouch doing its job of holding everything away from the body rather than compressing it. Leg length scales with the size too, so the anti-chafe coverage that stops fabric riding up between your thighs works as intended rather than sitting too short on a bigger frame.
If your trouser size and your SLY Collective size don’t match, that’s normal. As buying guides for pouch-style underwear point out, a Medium in one brand can sit closer to a Large in another, so chart-specific measuring beats relying on your jeans size every time.
Should I size up or down for the hammock pouch?
A hammock pouch fits differently to a standard brief or boxer, and that changes how you should read “tight” or “loose” against your usual size instincts.
Standard briefs rely on stretch fabric compressing everything against the body. The anatomical hammock pouch instead creates a sling shape that holds you slightly away from the body, so a well-fitted pouch can feel roomier at the front while the waistband and legs still sit snug. Don’t downsize just because the pouch feels less compressive than what you’re used to.
- Daily wear: true to your measured size is usually right, since the pouch is doing its job at rest and during normal movement.
- Sport or high movement: consider sizing down slightly for a firmer hold that reduces bounce during exercise.
- Sleep or recovery: many men prefer sizing up for maximum airflow and zero pressure, particularly useful for temperature control and comfort.
- Travel or post-surgical support: size according to the firmer end of your range, since a slightly closer fit keeps everything stable through long days of sitting or movement.
Longer leg panels are built into every size band to stop the classic ride-up problem, so you shouldn’t need to size up purely to get more leg coverage. That’s already engineered into the cut.
Pro Tip: Bamboo fabric has natural give and softens with wear, so a pair that feels a touch firm on day one usually relaxes slightly after a few washes. Wash in cool water and skip the dryer’s high heat to keep that stretch behaving predictably over time.
Bamboo viscose is prized for its combination of softness and breathability, which is part of why it holds its shape reasonably well wash after wash compared with stiffer synthetic blends, but expect a small amount of natural settling in the first few wears.
What to do if the fit is wrong
Got a pair that’s not quite right? Work through this before you go anywhere near a return form.
- Re-measure your waist properly. Standing, breathing normally, tape level front and back, no clothing bulk underneath.
- Compare that fresh number against the chart again, checking you read the correct column and didn’t round the wrong way.
- Check the waistband for stretch fatigue if this is a pair you’ve worn a few times. Elastic that’s loosened through wear reads differently to a new pair straight out of the packet.
- Cross check against a pair of trousers you know fits well, as a sanity check rather than a sizing method.
- If it’s still wrong, get in touch with SLY Collective for an exchange. Have your waist measurement and the size you ordered ready, since that speeds up the recommendation for your replacement.
Photos of the fit issue help if it’s a construction concern rather than a sizing one. For straightforward size swaps, your measurement plus your original order number is usually all support needs to sort a replacement.
Why SLY Collective builds sizing around the pouch, not just the waist
Most underwear charts exist purely to fit a waistband. Ours exists to fit a pouch, because the anatomical hammock pouch only does its job, supporting natural positioning and helping with temperature regulation, when the size is right for your body, not just your trouser size.
That’s the thinking behind pairing every size with proportional pouch depth and leg length rather than scaling the waistband alone. It’s also why we lean on bamboo fabric: it needs to move with the body through a full day, not just look good in the packet. One of our styles is made in Australia, reflecting the same attention to construction the brand has carried since 2005.
Get the waist measurement right and the rest of the design does the work it was built to do.
— Sharon
Get your size right the first time
There’s no guesswork required here, and no need to eyeball it against whatever brand you’re currently wearing. Grab your tape measure, check your waist against the official SLY Collective size chart, and order with confidence rather than crossing your fingers.
As a rough starting point: waist measurements generally fall into Small to Medium and Medium to Large size ranges, but always confirm against the live chart since exact cutoffs vary by style. Browse the full men’s pouch underwear range to see the anatomical hammock pouch, anti-chafe design and longer legs in action across every size.
Still unsure which way to round? SLY Collective offers exchanges if your first pick isn’t quite right, so there’s no real risk in ordering your best-measured size today and adjusting from there if needed.
FAQ
What waist measurement should I use for SLY Collective sizing?
Use your natural waist, measured where your trousers normally sit, not your belly button height or your hip measurement.
Does SLY Collective’s chart use centimetres or inches?
The chart lists both, but centimetres are the more precise column to check against, especially if your measurement sits near a size boundary.
What if my waist measurement falls between two sizes?
Size up if you want a looser pouch with more room and airflow, or size down for firmer support, particularly for sport or activity.
Does bamboo fabric change how the fit feels over time?
Slightly. Bamboo viscose softens a little with wash cycles, so a snug pair often relaxes into a more comfortable fit after the first few washes.
Can I exchange SLY Collective underwear if the size is wrong?
Yes. Re-measure first, compare against the chart, then contact SLY Collective with your measurement and order details to arrange an exchange.
Does the hammock pouch fit differently to standard briefs?
Yes. It creates a sling shape that holds you slightly away from the body rather than compressing everything flat, so it can feel roomier at rest even at your correct size.