The phrase "worsted weight yarn" refers to medium-weight yarn which is heavier than DK yarn / double knitting yarn, sports weight yarn, baby weight yarn, fingering weight yarn or crochet thread; it is lighter than chunky yarn or bulky yarn.
The packaging of worsted weight yarn is sometimes labeled with a yarn symbol featuring a prominent number 4 in the center, with the word "medium" appearing underneath.
The symbol is part of a series of symbols which has been popularized by the Craft Yarn Council and is used by yarn manufacturers who comply with the Craft Yarn Council's system of yarn weight standards. Not all manufacturers use their symbols or the CYC's system.
The Craft Yarn Council's Standard Yarn Weight System
Without a unified standard for yarn weights, it would be difficult for those who use, distribute and manufacture yarns to describe new or unfamiliar yarns to each other. Such a standard is helpful for crafters when they peruse yarn-related websites, publications, newsletters and other communications. With that in mind, the Craft Yarn Council has developed a standard yarn weight system; this system is in use by some yarn manufacturers, publishers, designers, and crafters.
Popularity of Worsted Weight Yarn
Several large-scale yarn manufacturers and retailers proclaim that worsted weight yarn is their most popular weight for knitting and crocheting.
Coats and Clark claims that their worsted weight Red Heart Super Saver has been the USA's best-selling yarn for more than a 70-year time span.
Who Uses Worsted Weight Yarn? What Is It Used For?
Worsted weight yarn appeals to crochet enthusiasts, knitters, weavers, textile artists and crafters for use in a wide variety of projects.
Recommended Hook Sizes for Crocheting With Worsted Weight Yarn
There are no hard-and-fast rules about what hook size you have to use with any given yarn weight; hook size is a matter of preference. Everyone's crocheting varies to a certain degree, which means that your preferred hook size might (or might not) be a little different than another crocheter's. Also, the hook size you want to use might vary considerably, depending on the type of project you are trying to crochet.
- If you desire a tight, stiff fabric perhaps a size G hook, or maybe even an F hook, would be appropriate, depending on what you have in mind -- for example, if you want to try crocheting amigurumi or other types of toys. When crocheting amigurumi, you don't want fluffs of stuffing coming through the fabric, and the item needs to hold its shape.
- When crocheting potholders and similar projects, which need to be tight enough to provide insulation yet somewhat flexible, I generally like to use an H hook, which would usually be in the neighborhood of 5.0 mm, depending on hook manufacturer.
- If you want to crochet a drapey, flexible fabric, a larger crochet hook is the way to go -- perhaps a hook in the I / J / K range would work to achieve your objective.
- When I first learned to crochet, I always used a size G crochet hook with worsted weight yarn. Not surprisingly, my early crochet work was tight and stiff. I eventually became adept at crocheting more loosely with the size G hook, but for me, that was just not the ideal hook size to use under most circumstances. See also: lessons I learned from my favorite crochet hook.
- When working Tunisian crochet with worsted weight yarn, I've been using a size J Tunisian crochet hook. That tends to create a seriously thick fabric. In many cases, a larger hook would be an improvement; large Tunisian crochet hooks are on my "wish list" for future purchase.
- When crocheting with multiple colors using the tapestry crochet technique, I might -- or might not -- vary my hook size considerably, depending on the project and what I am trying to achieve with it.
- When crocheting with worsted weight yarn, the Craft Yarn Council recommends using a hook in the 5.5 — 6.5 mm size range (I–9 to K–10 1⁄2.) Learn more here.
Wool Processing and Spinning: Worsted vs. Woolen
The word "worsted" does not always refer to a yarn weight. It can also refer, among other things, to a method of processing wool -- the worsted method, as opposed to the woolen method. The distinctions might be of interest to spinners, textile designers, textile engineers, yarn manufacturers, and educators, but isn't strictly a necessary part of the average crocheter's knowledge base.