Crochet hook sizes
I started with the list of knitting needle sizes, but soon found that I also needed to frequently check crochet hook sizes.
Steel crochet hooks
Aluminum crochet hooksI've found different charts for aluminum hooks with conflicting information on them, hence the different numbers in the columns below. Apparently, this is sometimes due to manufacturing inconsistencies, and other times it's because the manufacturer has changed the size. To avoid confusion, make sure you have a hook size gauge handy. As Dave likes to say, the nice thing about standards is that there are so many to choose from.