Measuring Your Hat Size
To find your general Hat Size using a flexible tape, measure your head circumference in CM above the ears, approximately 1 inch above your eyebrows and about ½ inch to 1 inch above the ears (as hat brim should not touch your ears). Note: The UK and US have traditionally used Imperial Sizes (measured in 1⁄8 increments) that are are out of phase by one unit with each other. To prevent confusion please always use CM to measure your size.
|52||20 & 1⁄2||6 & 3⁄8||6 & 1⁄2||59||23 & 1⁄4||7 & 1⁄4||7 & 3⁄8|
|53||20 & 7⁄8||6 & 1⁄2||6 & 5⁄8||60||23 & 5⁄8||7 & 3⁄8||7 & 1⁄2|
|54||21 & 1⁄4||6 & 5⁄8||6 & 3⁄4||61||24||7 & 1⁄2||7 & 5⁄8|
|55||21 & 5⁄8||6 & 3⁄4||6 & 7⁄8||62||24 & 3⁄8||7 & 5⁄8||7 & 3⁄4|
|56||22||6 & 7⁄8||7||63||24 & 3⁄4||7 & 3⁄4||7 & 7⁄8|
|57||22 & 1⁄2||7||7 & 1⁄8||64||25 & 1⁄8||7 & 7⁄8||8|
|58||22 & 7⁄8||7 & 1⁄8||7 & 1⁄4||65||25 & 5⁄8||8||8 & 1⁄8|
Headwear Size vs Hat Size
Different types of headwear are worn in different positions on the head, a person actually has multiple Headwear Sizes depending what is type of headwear is being worn and the circumference around the head where the headwear is positioned at. Using the initial Hat Size as a Baseline (as measured above), one can extrapolate some general rules of thumb (or maybe rules of head!) to find the other probable headwear sizes without having to measure them all.
Subtract one size for Berets and Boater Size (As usually worn higher on head)
Use the standard Hat Size for Top Hats/Bowlers/Fedoras/Panamas and most hats
Add one size for Tweed / Flat Cap Size (Usually worn at a longer slanted angle behind the ears)
Add two sizes for Winter Headwear Size (That go over the ears increasing the overall size)
The above image represents the Boater Size the Hat Size the Flat Cap Size and the Winter Headwear Size Positions