Ensure your tape measure is snug – Hats should fit snuggly; not too tight or too loose.
To measure your head circumference, wrap a tape measure around the widest part of your head – over your hair, from your forehead, above your ears, and around the back, then round to the front again.
Different hat styles have different lengths, but you should know the size of your head in relation to the pattern, so you know what to expect and what an ideal length for hats would be.
To measure your crown length measure from the crown to the base of your ear.
Head sizes vary from person to person, the chart of measurements is just an average. Measure your head to be sure; one size doesn’t fit all.
Negative ease concerning your hat means that the finished hat circumference measures smaller than the head circumference of the intended wearer.
The importance of negative circumference is crucial to how well a hat will fit. If you knit your hat to your exact measurements, you’ll have an ill-fitting hat that won’t stay on, and constantly fall down over your eyes.
To obtain a hat that fits, you will need to knit a gauge swatch to ensure you’re achieving the same sized gauge as the designer.
Generally, hat patterns are knit in the round. Therefore, ensure you’re knitting your gauge swatch in the round. Knitter’s gauge often changes between working flat and working in the round due to the purl rows when working flat.
As always, you want to treat your gauge swatch in the same washing manner as your finished object. Knitting your swatch and measuring without soaking/washing won’t give you an accurate gauge. Stitches tend to change like a gremlin when water is applied.