About the Crochet Hook Converter

Crochet hook sizes are labeled differently around the world: letter sizes in the US (H/8, G/6), metric millimeters elsewhere. Because US letter labels can vary slightly by brand, the millimeter gauge is the ground truth — this converter maps any size to both systems and the standard US hook range.

Choosing the Right Hook

Match the hook to your yarn's recommended gauge: fingering weight uses 2–4 mm hooks, worsted weight 5–5.5 mm, and bulky or jumbo yarns 8 mm and up. Swatching first always beats guessing.