Source : Craft Yarn Council
Categories of yarn, tension range, needle and hook size requirements for each.
I’ve spoken of it often, but never showed you what I meant here. This system created by the Craft Yarn Council offers a standardized way of looking for the proper yarn size for a given project. American yarn manufacturers tend to use this, and internationally it’s slowly happening too. If the band on the yarn you’re purchasing doesn’t mention a 0 to 6 standardized size, you can check out the type of yarn, the tension range, or needle or hook size recommended. At least some of this info will be available to help you pick right.
You really should visit the Craft Yarn Council website a lot, and often : it’s full of very useful info for us addicts.
Yarn Weight Symbol & Category Names |  |  |  |  |  |  |  |
|---|---|---|---|---|---|---|---|
Type of Yarns in Category | Fingering 10-count crochet thread | Sock, Fingering, Baby | Sport, Baby | DK, Light Worsted | Worsted, Afghan, Aran | Chunky, Craft, Rug | Bulky, Roving |
Knit Gauge Range* in Stockinette Stitch to 4 inches | 33–40** sts | 27–32 sts | 23–26 sts | 21–24 st | 16–20 sts | 12–15 sts | 6–11 sts |
Recommended Needle in Metric Size Range | 1.5–2.25 mm | 2.25— 3.25 mm | 3.25— 3.75 mm | 3.75— 4.5 mm | 4.5— 5.5 mm | 5.5— 8 mm | 8 mm and larger |
Recommended Needle U.S. Size Range | 000–1 | 1 to 3 | 3 to 5 | 5 to 7 | 7 to 9 | 9 to 11 | 11 and larger |
Crochet Gauge* Ranges in Single Crochet to 4 inch | 32–42 double crochets** | 21–32 sts | 16–20 sts | 12–17 sts | 11–14 sts | 8–11 sts | 5–9 sts |
Recommended Hook in Metric Size Range | Steel*** 1.6–1.4 mm | 2.25— 3.5 mm | 3.5— 4.5 mm | 4.5— 5.5 mm | 5.5— 6.5 mm | 6.5— 9 mm | 9 mm and larger |
Recommended Hook U.S. Size Range | Steel*** 6, 7, 8 Regular hook B–1 | B–1 to E–4 | E–4 to 7 | 7 to I–9 | I–9 to K–10 1⁄2 | K–10 1⁄2 to M–13 | M–13 and larger |
| * GUIDELINES ONLY: The above reflect the most commonly used gauges and needle or hook sizes for specific yarn categories.
** Lace weight yarns are usually knitted or crocheted on larger needles and hooks to create lacy, openwork patterns. Accordingly, a gauge range is difficult to determine. Always follow the gauge stated in your pattern. *** Steel crochet hooks are sized differently from regular hooks—the higher the number, the smaller the hook, which is the reverse of regular hook sizing |
