Men's Shirt Size Calculator
| Collar size | Neck (in) | Sleeve pair | Fits sleeve (in) |
|---|---|---|---|
| 14.5 | 14-14.4 | 30/31 | 29.5-31.4 |
| 15 | 14.5-14.9 | 31/32 | 30.5-32.4 |
| 15.5 | 15-15.4 | 32/33 | 31.5-33.4 |
| 16 | 15.5-15.9 | 33/34 | 32.5-34.4 |
| 16.5 | 16-16.4 | 34/35 | 33.5-35.4 |
| 17 | 16.5-16.9 | 35/36 | 34.5-36.4 |
| 17.5 | 17-17.4 | 36/37 | 35.5-37.4 |
| 18 | 17.5-17.9 | 37/38 | 36.5-38.4 |
Dress shirts are sized in two measurements - neck and sleeve - and the label reads like coordinates: 15.5/34 means a 15.5-inch collar with 34-inch sleeves. This calculator takes your two measurements and hands back the size to ask for, including the half-inch of collar slack that separates a shirt you can button from one you can breathe in.
Bottom line: measure neck at the base with one finger's width of slack under the tape, round up to the nearest half-inch, and that number IS your collar size - a 15.75-inch neck buys a 16. Sleeve runs from the center back of your neck, over the shoulder and down the arm to the wrist bone with the elbow bent - most men land between 32 and 36, and the odd pairing 33/34 covers a huge share of shirts off the rack.
The honest part: collar sizes are more honest than the rest of menswear because they are actual inches of actual shirt, but sleeves are graded in pairs (32/33, 34/35) by most brands, and fits - slim, regular, classic - reshape everything below the collar without touching the label. The neck number is the one to protect: a wrong sleeve drapes oddly, but a wrong collar strangles.
How to use
- Measure neck at the base, tape snug but with one finger slipping easily underneath, then round up to the next half-inch.
- Measure sleeve from center back neck, over the shoulder and elbow (arm bent), to the wrist bone - a second person makes this twice as accurate.
- Read the label pair and the fit note - slim cuts size down in the waist, classic cuts leave room; the collar coordinates never change.
Frequently asked questions
How do I know my dress shirt collar size?
Wrap a soft tape around the base of your neck where the collar would sit, snug enough that one finger slides under comfortably, and round up to the nearest half-inch - a 15.75-inch neck is a 16. The finger is the fit: no finger means the collar will strangle after lunch, two means it will gape. If you own a shirt that already fits, measure its collar laid flat from button-center to button-end and add nothing - that number already includes the maker's slack.
How is shirt sleeve length measured?
From the center back of your neck (that bony knob at the base), over the top of the shoulder, down the outside of the arm with the elbow bent at 90 degrees, ending at the wrist bone - the bend matters because bent-arm measurement bakes in the fabric a straight arm would steal when you reach forward. Most brands sell sleeve pairs (32/33, 34/35); take the pair your measurement sits in, or buy exact-sleeve shirts if your arms are a half-inch off the pair's midpoint.
What is the difference between slim, regular and classic fit?
The collar and sleeve numbers are identical across fits - what changes is the fabric below the chest: slim tapers 3-4 inches through the waist (tucked, crisp, unforgiving on the midsection), regular leaves 4-6 inches (the default that neither flatters nor punishes), and classic leaves 6-8 (untucked-friendly, billowy when tucked). The honest test is the button strain test: if any button gapes when you cross your arms, the cut is too slim for your build regardless of what the size chart claimed.
Why do my shirts shrink and what size compensates?
Cotton shrinks most on the first wash - about 1-2% in the collar and sleeve, which is a quarter-inch on a 15.5 collar and half an inch on a 34 sleeve - unless the fabric is pre-shrunk or the cotton-poly blend holds shape. Buy cotton shirts that fit comfortably new, wash cold and dry low or hang-dry, and the shrinkage stays inside the collar's half-inch slack. If a shirt only fits straight from the package, it will not survive its first laundry cycle - the maker spent the slack on the label instead of the shirt.