Posted on August 21 2026
Here's a test. Put on your dress shirt, do up the top button, and slide two fingers inside the collar. If there's room for three, your collar is too large. If you can't get one in, it's too small.
Most men fail this test in the same direction. Somewhere along the way they bought a shirt that felt comfortable in the shop and it's been too big ever since.
The two numbers that matter
Dress shirts are sold by neck and sleeve, in that order. A 16/34-35 shirt has a 16 inch collar and a 34 to 35 inch sleeve.
Neck. Measure around the base of the neck where a collar sits, keeping the tape snug but not tight, then add half an inch. Round up to the nearest half size.
Sleeve. Measure from the centre back of your neck, across the shoulder, down the outside of a slightly bent arm to just past the wrist bone. That's your sleeve length. Don't measure with a straight arm, because you don't live with a straight arm.
European brands size the collar in centimetres. A 16 inch collar is a 41. Add roughly 2.5cm per half inch from there.
What fit actually changes
Fit names change the body and the sleeve, not the collar.
Classic or regular fit has the most room through the chest and waist, with a fuller sleeve. It suits broader builds and anyone who wants no restriction.
Slim or fitted body takes roughly two to four inches out of the waist and narrows the sleeve. It removes the billowing at the back that classic fit produces on slimmer men.
Extra slim or slimline goes further and is genuinely tight on most men. Try before committing.
The mistake to avoid: buying a larger collar to get more room in the body. Buy your correct collar size and change the fit instead.
The four-point check in the mirror
Shoulder seam. It should sit exactly on the edge of your shoulder bone. Too far down the arm and the shirt is too big. This is the one thing that cannot be altered.
Chest. With the shirt buttoned, you should be able to pinch two to three inches of fabric at the side. Less is tight, more is loose.
Sleeve. The cuff should end where your wrist meets your hand, so that half an inch shows past a jacket sleeve.
Length. Long enough to stay tucked when you raise your arms. Untucked shirts should end mid-fly, but a true dress shirt is not designed to be worn untucked at all.
Fabric changes the fit
A shirt with elastane feels a half-size larger than the same size in rigid cotton. A heavily starched poplin feels smaller. This is why trying on matters more than the label.
Shrinkage, honestly
A quality shirt is pre-shrunk and will lose perhaps a quarter inch in the collar over its life, mostly in the first three washes. A cheaper shirt can lose a full size. If you're buying well, size for now rather than sizing up for shrinkage.
A few we're fitting men into
- Horst Light Blue Micro Diamond Performance Dress Shirt
- 7 Downie St. Dress Shirt LT10
- Klauss Pink Micro Dot Dress Shirt
Come get measured
It takes four minutes and most men discover they've been buying the wrong size for years. We'll write the numbers down so you have them for good.
Browse dress shirts or visit us in Markham.
Common questions
How do I know my dress shirt size?
Two numbers: neck and sleeve. Measure the neck where the collar sits, add a finger's width, and measure sleeve from the centre back of the neck to the wrist bone.
Should a dress shirt be tucked?
If it has a long tail and a curved hem, it was made to be tucked. A straight hem that ends at the hip is designed to be worn out.
How much shirt cuff should show past a jacket?
About a centimetre, roughly half an inch. Any more looks careless, any less looks like the jacket is borrowed.
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