The size of knitting needles that you will need to use for your project will depend on the weight of yarn that you are using. The lighter the yarn weight, the thinner the yarn, and the smaller the needles you will need to use. Equally, the heavier the yarn weight, the thicker the yarn, and the larger the needles you will need to use. You can generally use a few different sizes of needle for each yarn weight, depending on how tightly you knit and how loose you want the texture to be on your finished item. Sometimes patterns will call for needles that fall outside of the recommended size for the yarn weight, and this is usually down to a design element.

Yarn Weight UKYarn Weight USAYarn Weight AUSRecommended Needle Size
1 plyLaceweight2 ply1.25 – 3.00 mm
2 plyFingering3 ply1.25 – 3.50 mm
3 plySock3 ply2.00 – 3.50 mm
4 plySport5 ply3.25 – 4.00 mm
DKDK / Light Worsted8 ply4.00 – 5.00 mm
AranWorsted10 ply4.50 – 6.00 mm
ChunkyBulky12 ply5.00 – 8.00 mm
Super ChunkySuper Bulky14 ply8.00 – 12.00 mm