Measure a man's shoulders with a tape measure and a friend

Short answer: You measure shoulder width best with a soft tape measure and a friend who holds it in the right place. Stand relaxed and have your friend measure from the outer edge of one shoulder across the upper back to the other. Here is how to do it at home, step by step.

Why shoulder width matters

The shoulder seam should sit where your shoulder ends if a garment is to fit well. If it sits too far out the sleeve hangs, and if it sits too far in it pulls. That makes shoulder width one of the most useful measurements when you buy, without having to try everything on in a shop.

What you need

You need a soft tape measure of the kind tailors use and a friend who is willing to help. A rigid tool from the workshop is no good, because it does not follow the shape of the body. Put on a thin T-shirt so the measurement is realistic, and write the number down on paper or in your phone as you go.

Stand the way you normally do

Stand with your arms relaxed at your sides and look straight ahead. Do not pull your shoulders up or back, or the number will come out too big or too small. Your friend stands behind you with the tape and can see both shoulders. Breathe normally and stand still while they measure.

Find the outer points of the shoulders

The outer point of the shoulder is the bony edge at the top of the upper arm, where the shoulder turns into the arm. Your friend can feel for it with their fingers while you lift your arm a little and lower it again. That shows where the measurement starts and ends. Some people mark the points with pencil on an old T-shirt.

Measure across the back

Your friend places the zero end of the tape at one point and draws it across the upper back to the other, so the tape follows the shape of the body. It should lie flat and be tight enough not to sag, but not so tight that it presses. Read the number and measure twice if you like.

Compare with a garment that fits

If you have a T-shirt that fits well, lay it flat and measure from shoulder seam to shoulder seam. That is a good check on your own measurement. Compare with the size guide, and check it also if you are looking at the range for men, so you know which size to start with.

When the number falls between two sizes

If your shoulder width falls between two sizes, think about how you want to wear the garment. For several layers the larger one may fit better, and for a slim fit the smaller one may be better. Look at chest size and sleeve length too, and read about bamboo clothing for men to compare cuts.

Keep the number and reuse it

Write the measurement down and keep it, so you can use it the next time you buy clothes online. With long sleeve models it matters that the shoulder seam is right, so the sleeve falls correctly. Measure again if your body changes or you train more.

Frequently asked questions

How do I measure shoulder width at home

Stand relaxed in a thin T-shirt and have a friend measure from the outer edge of one shoulder across the back to the other. Use a soft tape measure and measure twice to be sure.

Why should a friend help

It is hard to reach your own back, and bending your arms changes the measurement. A friend can hold the tape flat and see that both points are right while you stand still.

What if my number falls between two sizes

Think about how you want the garment to sit. If you want some room or extra layers, choose the larger size, otherwise the smaller. Check chest and sleeve length as well before you decide.