Check out this video from Lion Brand Yarn for a primer on yarn weights!
Yarn comes in all different thicknesses, or weights. The standard yarn weight system goes from a range of 0 to 7, with size 0 (or lace yarn) being the smallest weight (or thickness) and size 7 being the largest weight. The standard yarn weight system on our website is a handy chart that provides the size needles and hooks you should use for each weight yarn, as well as suggested gauge.
The information provided reflects the most commonly used gauges and needle or hook sizes for specific yarn categories and are guidelines only (i.e., always follow the gauge stated in your pattern). The gauges provided are in the knit stockinette stitch to four inches and the single crochet stitch to four inches (unless otherwise noted).
Here’s some quick info about each yarn weight:
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Lace yarn (weight 0):
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Knitting needles: 1.5 to 2.25 mm, or sizes 000 to 1
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Crochet hook: Steel hooks that are 1.6 to 1.4 mm or a regular hook that is 2.25 mm
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Suggested gauge: 33 to 40 knit stitches; 32-42 double crochet stitches
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Types of lace yarn: fingering, 10-count crochet thread
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Super fine yarn (weight 1):
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Knitting needles: 2.25 to 3.25 mm, or sizes 1 to 3
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Crochet hooks: 2.25 to 3.5 mm, or sizes B-1 to E-4
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Suggested gauge: 27 to 32 knit stitches; 21 to 32 crochet stitches
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Types of super fine yarn: sock, fingering, baby
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Fine yarn (weight 2):
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Knitting needles: 3.25 to 3.75 mm, or sizes 3 to 5
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Crochet hooks: 3.5 to 4.5 mm, or sizes E-4 to 7
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Suggested gauge: 23 to 26 knit stitches; 16 to 20 crochet stitches
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Types of fine yarn: sport, baby
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Light yarn (weight 3):
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Knitting needles: 3.75 to 4.5 mm, or sizes 3 to 5
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Crochet hooks: 4.5 to 5.5 mm, or sizes 7 to I-9
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Suggested gauge: 21 to 24 knit stitches; 12 to 17 crochet stitches
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Types of light yarn: DK, light worsted
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Medium (commonly called worsted) yarn (weight 4):
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Knitting needles: 4.5 to 5.5 mm, or sizes 7 to 9
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Crochet hooks: 5.5 to 6.5 mm, or sizes I–9 to K–10 1⁄2
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Suggested gauge: 16 to 20 knit stitches; 11 to 14 crochet stitches
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Types of medium yarn: worsted, afghan, aran
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Bulky yarn (weight 5):
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Knitting needles: 5.5 to 8 mm, or sizes 9 to 11
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Crochet hooks: 6.5 to 9mm, or sizes K–10 1⁄2 to M–13
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Suggested gauge: 12 to 15 knit stitches; 8 to 11 crochet stitches
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Types of bulky yarn: chunky, craft, rug
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Super bulky yarn (weight 6):
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Knitting needles: 8 to 12.75 mm, or sizes 11 to 17
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Crochet hooks: 9 to 15 mm, or sizes M–13 to Q
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Suggested gauge: 7 to 11 knit stitches; 7 to 9 crochet stitches
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Types of super bulky yarn: super bulky, roving
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Jumbo yarn (weight 7):
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Knitting needles: 12.75 mm and larger, or sizes 17 and larger
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Crochet hooks: 15 mm and larger, or sizes Q and larger
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Suggested gauge: 6 knit stitches and fewer; 6 crochet stitches and fewer
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Types of jumbo yarn: jumbo, roving
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We recently updated the Standards & Guidelines to include the hand symbol. The HAND symbol can be used to represent gauge for yarns that do not require hooks and/or knitting needles, including, but not limited to, loop yarns and arm/hand knitting and crocheting yarns. This symbol can also be used on patterns to note that tools are not needed to complete the project.
And there you have it! Now take your new knowledge and share it with the world!