Free knitting & crochet tools

Yarn Weight Converter

Lost the label? Measure wraps per inch, or use the gauge or tool size you know, and find out whether that yarn is fingering, DK, worsted or bulky, and what a UK or Australian pattern would call it.

Yarn weight chart

CYCWeightAlso calledKnit gaugeCrochet gaugeNeedlesHooksWPI
0Lacecobweb, thread, 1–3 ply (UK/AU)33 to 4032 to 421.5 to 2.25 mm1.6 to 2.25 mm18 to 30
1Fingeringsuper fine, sock, 4 ply (UK/AU)27 to 3221 to 322.25 to 3.25 mm2.25 to 3.5 mm15 to 17
2Sportfine, baby, 5 ply (UK/AU)23 to 2616 to 203.25 to 3.75 mm3.5 to 4.5 mm13 to 14
3DKlight worsted, 8 ply (UK/AU)21 to 2412 to 173.75 to 4.5 mm4.5 to 5.5 mm11 to 12
4Worstedaran, afghan, 10 ply (UK/AU)16 to 2011 to 144.5 to 5.5 mm5.5 to 6.5 mm9 to 10
5Bulkychunky, craft, rug, 12 ply (UK/AU)12 to 158 to 115.5 to 8 mm6.5 to 9 mm7 to 8
6Super bulkysuper chunky, roving, 14 ply (UK/AU)7 to 116 to 98 to 12.75 mm9 to 16 mm5 to 6
7Jumboarm-knitting, giant roving1 to 61 to 512.75 to 25 mm16 to 25 mm1 to 4

Gauges are stitches over 4 inches: stockinette for knitting, single crochet for crochet. Ranges follow the Craft Yarn Council standard; WPI bands are approximate and vary with how tightly you wrap.

How to measure wraps per inch

Wrap the yarn around a ruler, a pencil or a WPI tool so the strands sit side by side, touching but not overlapping and not pulled tight. Count how many wraps fit in one inch. Do it twice from different parts of the skein and average. A worsted yarn gives about 9 to 10 wraps, a fingering yarn around 15 to 17. The result depends more on your wrapping tension than you'd expect, so treat it as a category, not a precise number, and confirm with a swatch before starting anything large.

Weight names around the world

American patterns use the Craft Yarn Council categories 0 to 7 and names like fingering, sport, DK and worsted. British and Australian patterns describe yarn by ply: 4 ply is fingering, 8 ply is DK, 10 ply is worsted or aran, 12 ply is bulky. The ply number was once a real count of strands but hasn't been for decades, so a modern "4 ply" is a thickness, not a construction. The chart above lists both sets of names.

Two categories cause most of the confusion. "Aran" sits at the heavy end of worsted, so an aran pattern worked in a light worsted yarn comes out small. And "DK" is called light worsted in some American yarn lines, which is not the same as worsted. When substituting, match the gauge on the label to the gauge in the pattern rather than matching the name.

Substituting yarn

A substitute needs to match gauge first and yardage second. Once you've identified the weight, check that its recommended gauge overlaps the pattern's, then compare yards per gram: a heavier yarn of the same weight category (more grams for the same yardage) usually means a denser fibre and a heavier finished piece. The yardage calculator will tell you how many skeins of the new yarn you need, and the gauge calculator what to do if the swatch comes out a little off.