Fit & sizing
Dress Shirt Sizes Explained: Collar, Sleeve and Fit
Dress shirt sizes explained: what 16 34/35 means, how to measure collar and sleeve length, EU and US collar sizes, slim vs regular fit and a fit checklist.
How Should a Suit Fit? A Mirror Checklist From Top to Toe
How should a suit fit? Check shoulders, collar, chest, button stance, sleeves, jacket length and trousers in the mirror, and learn what a tailor can change.
A suit fits well when the shoulder seams end at the edge of your shoulders without dents or overhang, the collar rests against your shirt collar, the buttoned jacket closes over the chest without an X-shaped pull, sleeves show a little shirt cuff, the jacket covers your seat, and the trousers sit at your waist and fall cleanly onto the shoe. Shoulders matter most because they are the hardest part to alter; almost everything else can be adjusted by a tailor.
Use this guide in the fitting room, in front of a full-length mirror, wearing the shirt and shoes you would wear with the suit.
Before you try it on: start with the right size
Men's suit jackets are sized by chest measurement. In the US and UK, the size is the chest in inches (40, 42); in continental Europe and Italy, it is roughly half the chest in centimeters (50, 52). A US/UK 40 is about an EU 50. The clothing size converter translates sizes between systems.
Take your chest, shoulder and sleeve measurements before shopping — our guide on how to measure yourself for clothes shows how. Also note the length fitting: short, regular or long, depending on your height and arm length.
The jacket, point by point
1. Shoulders
The shoulder seam should end at the edge of your shoulder bone.
- Too wide: the shoulder pad extends beyond your shoulder and collapses, creating a dent in the sleeve below.
- Too narrow: the sleeve head pulls, and you see a ripple or a bulge at the top of the arm.
Shoulder fit is very hard to alter. If the shoulders are wrong, try another size or another cut.
2. Collar
The jacket collar should lie flat against your shirt collar all the way round. If there is a gap at the back of the neck, or the collar rolls away when you stand naturally, the jacket does not suit your posture or shoulders. Some collar issues are fixable, but they need a skilled tailor.
3. Chest and buttoning point
Button the top button (on a two-button jacket) or the middle button (on a three-button jacket).
- The lapels should lie flat on your chest.
- The fabric should not pull into an X shape around the button.
- You should be able to slide a flat hand under the lapel without lifting the fabric.
An X-shaped pull means the jacket is too tight at the waist or chest. Large folds of loose fabric mean it is too big.
4. Back
Look over your shoulder in a mirror, or ask someone. The back should be smooth, without horizontal ripples (too tight) or vertical folds (too much fabric). If the jacket has vents, they should hang closed when you stand.
5. Sleeve length
With arms hanging naturally, the jacket sleeve typically ends at about the wrist bone, so a little shirt cuff — about a centimeter or a bit more — shows. This is one of the simplest alterations, unless the sleeves have working buttonholes at the cuff, which limits shortening.
6. Jacket length
A classic jacket covers the seat. Another traditional check: with arms relaxed, the hem falls around the middle of your hand. Shorter jackets look more contemporary but can make legs look shorter on taller men. Jacket length cannot really be changed without unbalancing the proportions.
The trousers
7. Waist and rise
Suit trousers should sit at your waist without a belt pulling them up. You should be able to slide two fingers in comfortably. The rise — distance from crotch to waistband — should let you sit and climb stairs without the trousers pulling.
8. Seat and thighs
Fabric should drape over the seat without sagging or pulling tight. In the thighs, there should be room to move without the fabric clinging or showing horizontal creases when you stand.
9. Leg width and break
The leg should fall in a clean line from the hip to the shoe. The break — the fold where trousers meet the shoe — is personal:
| Break | Look | Hem position |
|---|---|---|
| No break | Sharp, contemporary | Just touches the top of the shoe |
| Slight break | Clean, versatile | One small fold at the front |
| Medium break | Traditional | A clear single fold |
| Full break | Very traditional | Deep fold; can look sloppy on slim cuts |
What a tailor can change — and what not
| Easy and inexpensive | Possible, more work | Very hard or not worth it |
|---|---|---|
| Hem trousers | Taper trouser legs | Shoulder width |
| Shorten or lengthen sleeves (if enough fabric and no working buttonholes) | Take in or let out jacket waist | Jacket length |
| Take in or let out trouser waist (within the seam allowance) | Adjust collar | Moving the buttoning point |
| Move a button | Narrow lapels (rarely worth it) | Fixing a jacket that is two sizes too big |
The rule of thumb: buy for the shoulders and chest, tailor the rest.
Fit checklist for the fitting room
- Shoulder seams end at the shoulder bone, no dents or bulges
- Collar lies against the shirt collar
- Buttoned jacket shows no X-shaped pull
- Back is smooth; vents hang closed
- A little shirt cuff shows below the sleeve
- Jacket covers the seat
- Trousers sit at the waist without a belt holding them up
- You can sit, reach and climb stairs comfortably
- Trouser hem has the break you want
Fit and the occasion
How formal the suit needs to be depends on where you wear it. A dark navy or charcoal suit covers business, weddings and evening events, while lighter colors and softer construction suit daytime and summer occasions. Our guide to dress codes explained helps you match a suit to an invitation. If a suit is part of your everyday wardrobe, see how it fits into a men's capsule wardrobe.
Common mistakes
Buying too big "for comfort". An oversized jacket looks borrowed. A suit that fits well is usually more comfortable, because it moves with you.
Choosing by waist instead of shoulders. Waists can be taken in; shoulders cannot be fixed easily.
Skipping the sit-down test. Sit in the trousers and jacket in the fitting room. Pulling across the thighs or seat shows up immediately.
Wearing the wrong shirt to the fitting. Shirt collar and cuffs affect how the jacket collar and sleeves look. Bring a shirt that fits.
Ignoring posture. If you stand differently in the mirror than in real life, the fit will look different in real life. Stand naturally.
The takeaway
Fit is what makes an affordable suit look expensive and an expensive suit look careless. Start with the right size, prioritize the shoulders, check the details in the mirror, and budget a little for tailoring — the small adjustments are what make a suit look like yours.
FAQ
What is the most important part of suit fit?
The shoulders. They are the hardest and most expensive part to alter, so a jacket should fit well at the shoulders before you consider anything else.
How long should suit sleeves be?
Jacket sleeves usually end around the wrist bone, so that roughly a centimeter or a little more of shirt cuff shows when your arms hang naturally.
How long should a suit jacket be?
A classic jacket covers the seat of the trousers. With arms relaxed, the hem typically falls around the middle of your hand; contemporary cuts may be slightly shorter.
How much break should suit trousers have?
It is a style choice. No break or a slight break looks contemporary and clean; a medium break is more traditional. The trousers should not pool in folds over the shoe.