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Medium Weight Yarn (Worsted and Aran, CYC 4): Needle Size, Hook Size and Gauge

Last updated Researched from specs, manuals and owner reviews We earn from qualifying purchases
Quick answer

Worsted weight yarn, CYC 4, knits at 16 to 20 stitches per 4 inches on 4.5 to 5.5 mm needles and crochets at 11 to 14 single crochet on 5.5 to 6.5 mm hooks. It measures 9 to 12 wraps per inch and runs about 170 to 230 yards per 100 grams.

Yarn weight means the thickness of the strand, not how heavy the ball is. The Craft Yarn Council (CYC) numbers its categories from 0 for lace to 7 for jumbo, and worsted weight yarn is category 4. Labels also call it Worsted, Afghan, Aran. Its typical projects are afghans and blankets, hats, scarves, sweaters, dishcloths (cotton).

Worsted Weight Yarn (CYC 4) at a glance (CYC guidelines)
CYC category4 (Medium)
Other namesWorsted, Afghan, Aran
Wraps per inch9 to 12
Knit gauge (stockinette, per 4 in)16 to 20 stitches
Recommended needles4.5 to 5.5 mm (US 7 to 9)
Crochet gauge (per 4 in)11 to 14 single crochet
Recommended hooks5.5 to 6.5 mm (I-9 to K-10.5)
Yards per 100 g (retailer charts)170 to 230

What size knitting needles do you use for worsted weight yarn?

CYC recommends 4.5 to 5.5 mm (US 7 to 9) needles for worsted weight yarn. Every size below falls inside that range. Start in the middle and change size until your swatch matches the pattern gauge; each size links to its own page with cast-on estimates.

Knitting needles for worsted weight yarn
NeedleMetricUSOld UKAlso suits
US 74.5 mm77light (DK)
US 85 mm86Only this weight
US 95.25 mm9NoneOnly this weight
US 95.5 mm95bulky (chunky)

What size crochet hook do you use for worsted weight yarn?

CYC recommends 5.5 to 6.5 mm (I-9 to K-10.5) hooks for worsted weight yarn, at 11 to 14 single crochet per 4 inches. The smallest recommended hook is 1 mm off the smallest recommended needle, because crochet fabric is denser than knitting.

Crochet hooks for worsted weight yarn
HookMetricOld UKAlso suits
I-95.5 mm5light (DK)
J5.75 mmNoneOnly this weight
J-106 mm4Only this weight
K-10.56.5 mm3bulky (chunky)

How much worsted weight yarn do you need for a project?

These are planning ranges from published yardage guides for worsted weight yarn. Crochet figures run 25 to 33 percent above knitting. Skeins assume 100 gram skeins at 170 to 230 yards each.

Yardage by project in worsted weight yarn (planning estimates)
ProjectKnit (yd)Crochet (yd)100 g skeins, knit
Adult Hat200 to 225250 to 3001 to 2
Cowl200 to 300250 to 4001 to 2
Mittens150 to 250200 to 3251 to 2
Scarf375 to 500475 to 6752 to 3
Adult Socks275 to 375350 to 5002 to 3
Shawl375 to 550475 to 7252 to 4
Adult Sweater1,125 to 1,6251,400 to 2,1505 to 10
Baby Blanket1,000 to 1,1251,250 to 1,5005 to 7
Throw Blanket2,250 to 3,1252,825 to 4,15010 to 19
Twin Size Blanket4,100 to 5,7005,150 to 7,60018 to 34
Full Size Blanket5,000 to 6,9006,250 to 9,20022 to 41
Queen Size Blanket6,250 to 8,6507,800 to 11,50028 to 51
King Size Blanket7,500 to 10,4009,400 to 13,85033 to 62

Tools and yarn for worsted weight yarn

Prices change often, so confirm on Amazon. As an Amazon Associate we earn from qualifying purchases.

How many stitches do you cast on with worsted weight yarn?

These counts use the full CYC gauge range for worsted weight yarn: 16 to 20 stitches per 4 inches knit and 11 to 14 single crochet crocheted. Knit hat counts are rounded to a multiple of 4 for ribbing, and crochet counts add 1 turning chain. Treat them as estimates and swatch first.

Estimated stitch counts in worsted weight yarn
PieceKnit stitchesCrochet starting chain
Hat, 20 in around80 to 10056 to 71
Scarf, 8 in wide32 to 4023 to 29
Baby blanket, 42 in wide168 to 210117 to 148
Throw, 50 in wide200 to 250139 to 176
Queen blanket, 90 in wide360 to 450249 to 316

How do you identify worsted weight yarn by wraps per inch?

Wraps per inch (WPI) tells you the weight of an unlabeled yarn. Wrap it snugly around a ruler with the strands touching but not overlapping, count the wraps in one inch, and compare with the CYC ranges. Medium yarn measures 9 to 12 wraps per inch.

Yarn weight by wraps per inch
CYC weightWPIKnit gauge per 4 inYards per 100 g
0 lace30 to 40 or more33 to 40600 or more
1 super fine (fingering)14 to 3027 to 32380 to 600
2 fine (sport)12 to 1823 to 26300 to 380
3 light (DK)11 to 1521 to 24230 to 300
4 medium (worsted)9 to 1216 to 20170 to 230
5 bulky (chunky)6 to 912 to 15100 to 170
6 super bulky5 to 67 to 11under 100
7 jumbo1 to 46 or fewerNot published

Can you substitute worsted weight yarn for another yarn weight?

You can, as long as you match gauge. The last column shows what happens if you keep a pattern's stitch count for worsted yarn at 18 stitches per 4 inches but knit the neighboring weight at the middle of its CYC gauge range.

Substituting neighboring weights for worsted weight yarn
WeightKnit gauge per 4 inNeedlesSame stitch count comes out
Light (DK)21 to 243.75 to 4.5 mm (US 5 to 7)about 20 percent narrower
Medium (worsted)16 to 204.5 to 5.5 mm (US 7 to 9)This weight
Bulky (chunky)12 to 155.5 to 8 mm (US 9 to 11)about 33 percent wider

Estimates, not promises

Planning estimates only. The yardage stated on the pattern always wins. Buy 10 to 15 percent extra, from the same dye lot. The yarn substitution calculator works out how many skeins of a different yarn you need.

Frequently asked questions

What size knitting needles do you use for worsted weight yarn?

The Craft Yarn Council lists 4.5 to 5.5 mm (US 7 to 9) needles for worsted weight yarn, which is CYC category 4. Those are the most commonly used sizes, not a rule. Go down a size if your swatch has fewer stitches per 4 inches than the pattern, and up a size if it has more. Loose knitters often start one size smaller than the label suggests.

What size crochet hook do you use for worsted weight yarn?

CYC lists 5.5 to 6.5 mm (I-9 to K-10.5) hooks for worsted weight yarn, at a typical gauge of 11 to 14 single crochet per 4 inches. The smallest recommended hook is 1 mm larger than the smallest recommended knitting needle, because crochet fabric is denser. Many yarn labels print both a needle and a hook suggestion, and your gauge swatch has the final say.

What is the knitting gauge for worsted weight yarn?

CYC gives 16 to 20 stitches per 4 inches (10 cm) in stockinette on 4.5 to 5.5 mm (US 7 to 9) needles. At 18 stitches per 4 inches, a 20 inch wide piece needs about 90 stitches and a 20 inch hat about 92. Your hands, the fiber and the stitch pattern all shift gauge, so knit a 6 inch swatch, wash it and measure the center.

How many wraps per inch is worsted weight yarn?

Worsted weight yarn measures 9 to 12 wraps per inch (WPI) on the CYC scale. Wrap the yarn snugly around a ruler, strands touching but not overlapping, and count the wraps in one inch. The range overlaps light (DK) and bulky (chunky), so an unlabeled yarn near the edge needs a gauge swatch to confirm. Fuzzy yarns read thicker than they knit.

How much worsted weight yarn do I need for a blanket?

Published planning ranges put a throw blanket at about 2,250 to 3,125 yards to knit and 2,825 to 4,150 yards to crochet in worsted weight yarn. That is 10 to 19 skeins of 100 grams for knitting. A queen size blanket takes about 6,250 to 8,650 yards knit. Pattern yardage always wins, and buy 10 to 15 percent extra from one dye lot.

What can I substitute for worsted weight yarn?

The nearest weights are light (DK) and bulky (chunky). If you work a pattern written for worsted at 18 stitches per 4 inches with bulky (chunky) yarn at its typical gauge, the piece comes out about 33 percent wider. Match the pattern gauge with a swatch, not the weight name, and compare yards per 100 grams so you buy enough.

How we research: we compare manufacturer specifications, owner manuals, published standards and recurring themes in verified owner reviews. We do not test products in person, and this is researched guidance, not professional advice. Follow your machine manual and pattern, and take care with rotary cutters, hot irons and needles. As an Amazon Associate we earn from qualifying purchases.