Crochet Hat Size Chart — Every Size from Preemie to Adult

A crochet hat size chart gives you the target head circumference and hat height for each age or size category. The key number is head circumference — measure around the widest part of the head, just above the ears and eyebrows. Hat height is measured from the brim fold (or where the brim would sit) to the crown. Both measurements vary by construction method and crown shaping, so the chart provides a useful starting range rather than a fixed number.

Hat circumference is worked with negative ease — the finished hat measures 10–15% smaller than the head it fits. Negative ease creates the stretch needed to keep a hat on the head without using a brim tie. For a standard beanie, 10% negative ease is the default. For a slouchy hat, use 0% ease or slight positive ease. For a fitted earwarmer or skullcap, use 15–20% negative ease.

The stitch count calculator in this tool applies 10% negative ease automatically. Enter your gauge and the table updates with cast-on stitch counts for every size at once — useful if you are making a set of hats in multiple sizes with the same yarn and hook.

There are two main methods for constructing a crocheted hat. The rectangle method works flat from a rectangular piece of fabric: you chain the number of stitches equal to the hat height, work rows until the piece is as wide as the hat circumference, then seam the short edges together and cinch the top. This is the most beginner-friendly construction — you are always working in a straight line, counting is easy, and fixing mistakes is simple. The cast-on count in this chart is for the rectangle method.

The circle method (also called top-down) starts at the crown with a magic ring and increases outward until the circumference matches the head measurement minus ease. Different stitch types increase at different rates — double crochet adds 6 stitches per round for a flat crown in standard gauge. Once the crown circle reaches the correct circumference, you work even rounds straight down to the brim height. This method requires no seam and is the basis for most modern beanie patterns.

Both methods produce the same finished hat. The rectangle method is faster to learn and easier to adapt to any gauge. The circle method gives a seamless result and is better suited to color changes in the round. If your pattern says 'crochet hat size chart rectangle,' it is referring to the rectangular panel method and the width × height dimensions from the chart above.