Which Hook Do I Use?
Crochet hooks are available in different sizes to suit various yarns, and they’re identified by letters and/or numbers. The smaller the hook, the tighter the stitch. A crochet pattern will list a recommended hook size, but you may need to use a different size to obtain proper gauge. Make a gauge swatch using the recommended hook size, then adjust accordingly until you reach the right gauge.
Steel hooks are used for fine threads and yarns. They come in small sizes ranging from 00 (largest) to 14 (smallest).
Used for heavier yarns and threads, these “standard” crochet hooks are made from a variety of materials, with aluminum, plastic, and bamboo being popular choices. Which style you choose to use is a matter of personal preference. Sizes are usually identified by a letter-number combination or the hook size in millimeters, depending on whether the pattern lists the U.S. size or the metric conversion—many patterns list both. The most commonly used sizes are:
Afghan hooks have a hook on one side and a flexible nylon cord similar to a circular knitting needle, but with a stopper on one end. This specialty hook is used to work the afghan stitch.