Hook and Yarn Sizes – Conversion Table

Why do different countries have different names and gauges for EVERYTHING???
It’s so frustrating!!!

While tracking down patterns to crochet, as well as deciding on what thickness of yarn to use and what size hook to use, I get incredibly lost when I see things like ‘use a F hook’ and ‘use worsted weight yarn’. What does it all mean????

Hook sizes
In the US, they have a letter gauge system for their crochet hooks. Here in Australia, you will find all hooks are given a thickness in mm e.g. ‘3.5mm’:

Crochet Hook Size Conversion Table
Metric sizing (mm)	US Sizing
2.00	-
2.25	B
2.50	-
2.75	C
3.00	-
3.25	D
3.50	E
3.75	F
4.00	G
4.50	-
5.00	H
5.50	I
6.00	J
6.50	K
7.00	-
8.00	L
9.00	M
10.00	N

Yarn Types / Sizes Despite the fact that Australia, the UK and the US all speak English, all 3 have different names for yarn types. In Australia we tend to name our yarn based on what ply it is:

Yarn Type / Size Conversion Table
Australia	UK	US
1ply / 2 ply	1 ply / 2 ply	lace weight
2 ply / 3ply	2 ply / 3 ply	baby / fingering
3 ply / 4 ply	3 ply / 4 ply	sport / sock / light weight
8 ply	DK / double knit	light worsted
10 ply	Aran	worsted weight
12 ply	chunky	bulky
14 ply	super chunky	super bulky