Men's shirt size chart: collar in inches and cm

How to use the chart

1. Take a shirt whose collar fits you, lay the collar flat and measure from the centre of the button to the far end of the buttonhole. Or measure around your neck where the collar sits.
2. Choose collar in the finder and enter the measurement in inches, or choose exact centimetres. The finder highlights the first size that is large enough.
3. To convert a label, choose the label column and enter the number printed on the shirt.

The second chart converts sleeve lengths. Without JavaScript the finder is unavailable, but both charts are complete.

How the sizes are derived

The collar size is a length: the girth of the neck the shirt is made for. One inch is 2.54 cm, so 15.5 inches are 39.37 cm. Labels in whole centimetres print 39.

The rounded labels in the chart equal the chart of a large US shirt maker for all eight sizes from 14.5 to 18 inches. Note the jump from 39 to 41: 16 inches are 40.64 cm, which rounds to 41, so a label of 40 does not appear.

Some makers round to half centimetres instead. One UK retailer prints 38.5 for 15 inches and 41.5 for 16 inches.

Sleeve length

In the United States the sleeve length is measured from the centre of the back of the neck, over the point of the shoulder and down to the wrist, with the arm slightly bent. It is printed after the collar size: 15.5/34 means a collar of 15.5 inches and a sleeve of 34 inches.

Makers do not all measure sleeves from the same point. Check how the brand measures before you compare two lengths.

Worked example

The collar of a shirt that fits you measures 40 cm.

1. 40 divided by 2.54 is 15.75 inches.
2. The first collar that is large enough is 16 inches, which is 40.6 cm.
3. On a continental label look for 41.

Common mistakes

• Pulling the tape tight around the neck. A collar needs to close comfortably.
• Expecting a label of 40. With whole centimetre labels, 15.5 inches is 39 and 16 inches is 41.
• Taking the collar size as a guide to the chest. Shirts with the same collar come in different body cuts.
• Comparing sleeve lengths that are measured from different points.

Sources and checks

The values in the chart are calculated from the definitions in the sources below. They are not copied from another chart. Last checked against the sources on September 28, 2026.

The collar size is the neck girth in inches. The centimetre label is the same length rounded to the whole centimetre; the exact conversion is shown next to it.

The rounding reproduces the Brooks Brothers chart for all eight sizes from 14.5 to 18 inches. Sizes 14 and 18.5 follow the same rule and were not compared.

Some charts print half centimetres instead, for example 38.5 for 15 inches. These numbers are retail conventions, not a standard. Brands cut differently, and the same number is cut larger by some brands than by others. Use the size chart of the brand and its body measurements when you buy.

• Brooks Brothers, size guide for dress shirts

Used for: Collar sizes 14.5 to 18 inches with the centimetre label for each: 37, 38, 39, 41, 42, 43, 44 and 46.

• Charles Tyrwhitt, sizing guides

Used for: Shirts are sized by neck in inches from 14.5 to 18 and by sleeve length in inches from 33 to 37.

• ASOS, men's suits and tailoring size chart

Used for: UK size 40 is a chest of 40 inches, and UK shirts use the same collar scale in inches.

• L.L.Bean, men's size charts

Used for: How US sleeve length is measured: from the centre of the back of the neck over the shoulder to the wrist.