Yarn weight #5

Bulky weight yarn (#5)

Bulky yarn is category 5 in the Craft Yarn Council system, also called chunky, craft or rug yarn. Crocheters use a 6.5–9 mm hook, US K-10½ to M-13, and get 8–11 single crochet per 4 inches. Bulky yarn works up quickly into warm hats, scarves, cowls and throws.

By the crochetpatterns.io editorial team · Reviewed September 13, 2026 · Editorial policy

Bulky yarn at a glance
Detail	Value
CYC number	#5
Also called	Chunky, Craft, Rug, 12-ply (AU/NZ)
Crochet gauge	8–11 sc per 4 in / 10 cm
Hook size (mm)	6.5–9 mm
Hook size (US)	K-10½ to M-13
Yards per 100 g	about 80–150 yd
Best for	Chunky hats, Scarves and cowls, Quick throws, Rugs

What is bulky weight yarn called in the US and UK?

Bulky yarn is category 5 in the Craft Yarn Council system. You will also see it sold as chunky, craft, rug, 12-ply (au/nz). It typically runs about 80–150 yd per 100 g, though the exact length depends on the fibre.

How does bulky yarn compare with the weights either side?

Medium (#4) is one step finer and works up at 11–14 sc per 4 in / 10 cm. Super Bulky (#6) is one step thicker at 7–9 sc per 4 in / 10 cm. Moving one weight up usually means going up about one to two hook sizes.

Bulky yarn and neighbouring weights
Weight	Crochet gauge (4 in)	Hook (mm)	Hook (US)	Yards per 100 g
#4 Medium	11–14 sc per 4 in / 10 cm	5.5–6.5 mm	I-9 to K-10½	about 150–220 yd
#5 Bulky	8–11 sc per 4 in / 10 cm	6.5–9 mm	K-10½ to M-13	about 80–150 yd
#6 Super Bulky	7–9 sc per 4 in / 10 cm	9–15 mm	M-13 to Q	about 40–90 yd

What hook size should you use for bulky yarn?

Start with a hook between 6.5–9 mm (K-10½ to M-13). Standard hooks in that range are 6.5 mm (US K-10½), 7 mm, 8 mm (US L-11), 9 mm (US M/N-13). Go down a size for tighter fabric such as amigurumi, and up a size for drape.

What is bulky yarn best for?

Bulky yarn is a good choice for chunky hats, scarves and cowls, quick throws, rugs. Our library has 18 patterns in this weight, such as day and night shell stitch rug (vintage american thread), ribbed half double crochet chunky scarf, country home round rug (vintage american thread), dot dot dash rug (vintage american thread), happy the clown rug (vintage american thread).