STEP 1: Distract the child with a toy or food (so they don't try to help you!).
STEP 2: Use a measuring tape to take the measurement. Otherwise, use a ribbon to take the size then use a ruler to find the measurement.
ORIGINALS and SWIM collections: Choose a hat size closest to your child's measurement. These fabrics are very stretchy and will grow up to 4cms. For example: the child's head measures 41cms, you will need the 42cm size that will stretch another 4cms up to 46cms - giving plenty of future wear. Purchasing the next size up would be too large and block the child's vision.
HERITAGE collection: Heritage's woven fabric cannot stretch quite as much. We suggest purchasing a size larger to allow extra room for growth if wanting a longer length of fit. For example: for the Baby Flap Hat, if a baby's head measures 38cm, you will need the 42cm size - giving plenty of future wear. Please note: each style of Heritage has a different example in the Size Advice and Brim Depth tab under the product description to give you more guided advice.