IDK, what's DK?
Sport-weight and DK-weight yarn are the most-confused yarn weights in the shop, and there’s a lot of overlap between them. You sometimes even see that the yarn company has labeled the yarn one way and I’ve chosen to shelve it with a different category of yarn (Malabrigo Arroyo, I’m looking at you in particular).
According to the Craft Yarn Council, DK-weight yarn is a yarn that works up at 12-17 single crochet stitches per 10 cm / 4” or 21-24 stitches in stockinette per 10 cm / 4”. It is sometimes referred to as “light worsted” as well. An average hank of DK-weight yarn is 229 - 297 meters per 100 grams, or 250-325 yards per 3.5 ounces. In the shop, our DK-weight selection includes Berroco Spree, Berroco Vintage DK, Ella Rae Eco Tweed, and West Yorkshire Spinners ColourLab DK.
That’s all well and good, you might say. But let’s cut to the chase - what does “DK” stand for? DK is an abbreviation for “double knitting.” You may have run across this in the context of a knitting technique that produces a double-thick fabric (sometimes with knitted-in 2-color designs that are reversible and switch colors from one side to the other). In the case of the term applied to yarn weights, however, it has more to do with the physical structure of the yarn.
One of our most popular sock yarns (yes, true sock yarns) is West Yorkshire Spinners’ Signature 4-Ply. If you pick this yarn apart into its structural components, there are indeed 4 singles plied together to make one yarn. In Great Britain and many of the former and current countries of the British Commonwealth, you’ll often see fingering-weight yarn simply referred to as “4-ply.” DK-weight yarn is now often referred to as “8-ply” in those same areas… which is double the plies you find in the 4-ply yarn. Fingering-weight held double is thus - (4 plies x 2 strands) = 8-ply. When you hold it double to knit it at a larger gauge… you get “doubled knitting [or crocheting] yarn.” And if you’ve ever held fingering-weight double to substitute in for another weight of yarn, you’ll often find (depending on the original skein) that it’s about the same as a heavy DK-weight yarn.
And by and large, that seems to be about the entire story.
Sidebar - crocheters in the audience are likely crying foul that this shows the bias inherent in the system towards knitters. And you’re not wrong. However, it’s likely that this was the result of where crochet in Europe and North America was focused in the 19th- and early 20th-centuries: trims and laces. These pieces were often worked in fine thread, not larger yarns - larger yarns were generally reserved for knitting, or sometimes weaving. This tendency to distinguish between which yarns can be used for which crafts might also be reflected in any experience where you’ve heard a crocheter ask if the yarns in a given store can be used for crochet. In today’s yarn world, yes, of course! But crocheting with materials thicker than crochet thread - at least in the American and European practice of crochet - is a relatively recent development.
Lindsey Spoor is the owner of Stilly River Yarns in Stanwood, WA.