Yarn Weight Guide

0_LACE_3L

Category: LACE
Types of yarn in category: Fingering, 10-count, crochet thread.
Knit Gauge Range in Stockinette Stitch to 4 inches: 33-40 sts*.
Recommended Needle Size: 1.5–2.25 mm.
Crochet Gauge Ranges in Single Crochet to 4 inches: 32–42 double crochets*.
Recommended Hook Size: Steel** 1.6–1.4 mm.
* Lace yarn is typically worked with larger needles and hooks, and hence these gauges are simply guidelines. One should follow the gauge in the 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.

1_superfine_3L

Category: SUPER FINE
Types of yarn in category: Sock, Fingering, Baby.
Knit Gauge Range in Stockinette Stitch to 4 inches: 27-32 sts.
Recommended Needle Size: 2.25-3.25 mm.
Crochet Gauge Ranges in Single Crochet to 4 inches: 21-32 sts.
Recommended Hook Size: 2.25-3.5 mm.

2-fine_3L

Category: FINE
Types of yarn in category: Sport, Baby.
Knit Gauge Range in Stockinette Stitch to 4 inches: 23-26 sts.
Recommended Needle Size: 3.25-3.75 mm.
Crochet Gauge Ranges in Single Crochet to 4 inches: 16-20 sts.
Recommended Hook Size: 3.5-4.5 mm.

3-light_3L

Category: LIGHT
Types of yarn in category: DK, Light Worsted.
Knit Gauge Range in Stockinette Stitch to 4 inches: 21-24 sts.
Recommended Needle Size: 3.75-4.5 mm.
Crochet Gauge Ranges in Single Crochet to 4 inches: 12-17 sts.
Recommended Hook Size: 4.5-5.5 mm.

4-medium_3L

Category: MEDIUM
Types of yarn in category: Worsted, Afghan, Aran.
Knit Gauge Range in Stockinette Stitch to 4 inches: 16-20 sts.
Recommended Needle Size: 4.5-5.5 mm.
Crochet Gauge Ranges in Single Crochet to 4 inches: 11-14 sts.
Recommended Hook Size: 5.5-6.5 mm.

5-bulky_3L

Category: BULKY
Types of yarn in category: Chunky, Craft, Rug.
Knit Gauge Range in Stockinette Stitch to 4 inches: 12-15 sts.
Recommended Needle Size: 5.5-8 mm.
Crochet Gauge Ranges in Single Crochet to 4 inches: 9-11 sts.
Recommended Hook Size: 6.5-9 mm.

6-superbulky_3L

Category: SUPER BULKY
Types of yarn in category: Super Bulky, Roving.
Knit Gauge Range in Stockinette Stitch to 4 inches: 7-11 sts.
Recommended Needle Size: 8-12.75 mm.
Crochet Gauge Ranges in Single Crochet to 4 inches: 6-9 sts.
Recommended Hook Size: 9-16 mm.

7-jumbo_3L

Category: JUMBO
Types of yarn in category: Jumbo, Roving.
Knit Gauge Range in Stockinette Stitch to 4 inches: 6 or fewer sts.
Recommended Needle Size: 12.75 or more mm.
Crochet Gauge Ranges in Single Crochet to 4 inches: 5 or fewer sts.
Recommended Hook Size: 16 or more mm. 

 

Source of information: ys.com-rgb