Most knee sleeve returns have nothing to do with quality. They come down to one thing: the wrong size. And the wrong size almost always comes from measuring in the wrong place. Here is exactly how to measure, sleeve by sleeve.
Ask most lifters how they picked their knee sleeve size and the answer is usually some version of "I guessed" or "I went with my trouser size". Neither works.
A knee sleeve is a compression garment. It only does its job if it fits closely around the joint, and a centimetre or two either way is the difference between solid support and a sleeve that either cuts off circulation or slides down your shin mid-set.
The Mistake Almost Everyone Makes
People measure around the middle of the kneecap for every sleeve. For some sleeves that is right. For others it is wrong by several centimetres.
Different sleeves are built to grip the leg at different points, so they are measured in different places. That is why one brand's Medium can feel nothing like another's, and why our own sleeves do not all share one chart.
What You Need
- A soft tape measure (a phone cable or piece of string works too: wrap it, mark it, then lay it flat against a ruler)
- A pen to mark your reference point
- Two minutes, standing up, with your knee slightly bent
V3 7mm, V3 5mm and Straight Cuff Sleeves: 8cm Below the Middle of the Kneecap
- Stand up and bend your knee slightly.
- Find the middle of your kneecap and measure 8cm straight down from it.
- Wrap the tape all the way around your leg at that point. Snug, flat, not pulled tight.
Between two sizes? Size up. Our V3 sleeves fit tighter than most brands, and sizing down to "get more support" is the most common reason people struggle to get them on.
Stiff Knee Sleeves PRO: 10cm Below the Centre of the Kneecap
The PRO is measured differently because it is built differently. It is our stiffest sleeve, with minimal give, so accuracy matters more than with anything else in the range.
- Find the centre of your kneecap.
- Measure 10cm straight down from it.
- Measure around your leg at that point, as close to exact as you can. Do not round up or down.
The PRO chart also lists quad (10cm above the kneecap) and calf (widest point) measurements. Your knee measurement decides the size. Quad and calf confirm the sleeve will taper properly to your leg.
3mm Double Ply and Thermal Sleeves: Around the Kneecap
- Bend your knee to roughly 30 degrees.
- Wrap the tape around your knee, straight across the middle of the kneecap.
- Keep it flat and snug, then read the measurement.
Between two sizes? Size down. These lighter sleeves are designed to stay snug through long sessions, and a sleeve that is slightly loose will slip.
Elbow Sleeves: Around the Joint
If you are buying elbow sleeves at the same time, measure around the elbow joint with your arm hanging relaxed by your side. That single measurement decides your size.
Three Things That Throw Your Measurement Off
- Measuring sitting down. Your leg shape changes when you sit. Stand up.
- Measuring straight after training. A pumped quad or swollen knee will read bigger than normal. Measure on a rest day.
- Pulling the tape tight. You want the tape flat against the skin, not digging in.
Want to understand what tight should actually feel like once your sleeves arrive? Read Are Your Knee Sleeves Too Tight?
Find Your Sleeve and Your Size in Two Minutes
Still not sure which sleeve you need, or which chart applies to you? You do not need to work it out by hand.
Our Knee Support Buying Guide does both jobs in one place. Step 1 is a 30-second quiz that matches you to the right Mammal knee support for how you train. Step 4 is our size finder: pick your sleeve, follow the measuring steps for that exact product and it tells you your size.
Open the Knee Support Buying Guide ->
Every Mammal knee sleeve comes with 30-day free returns and a 12-month warranty, so if the fit is not right, we will sort it.