Yarn weight finder

The eight standard yarn weights, the gauge range for each, and a way to place an unlabelled yarn using wraps per inch.

Results update as you type.

The eight standard weights

Craft Yarn Council Standard Yarn Weight System, checked 22 October 2026. Gauge is given in stockinette for knitting and single crochet for crochet, over 10 cm / 4 in.

CategoryKnit gaugeNeedleUS needleCrochet gaugeHook
0 Lace 33–40 sts 1.5–2.25 mm 000–1 32–42 dc 1.4–2.25 mm
1 Super Fine 27–32 sts 2.25–3.25 mm 1–3 21–32 sts 2.25–3.5 mm
2 Fine 23–26 sts 3.25–3.75 mm 3–5 16–20 sts 3.5–4.5 mm
3 Light 21–24 sts 3.75–4.5 mm 5–7 12–17 sts 4.5–5.5 mm
4 Medium 16–20 sts 4.5–5.5 mm 7–9 11–14 sts 5.5–6.5 mm
5 Bulky 12–15 sts 5.5–8 mm 9–11 8–11 sts 6.5–9 mm
6 Super Bulky 7–11 sts 8–12.75 mm 11–17 7–9 sts 9–15 mm
7 Jumbo 6 sts or fewer 12.75 mm and larger 17 and larger 6 sts or fewer 15 mm and larger

Wraps per inch

WPI is the low-tech way to classify a yarn with no label. Wrap the yarn around a ruler for one inch, keeping the wraps touching but not stretched, and count how many fit. The table below is a practical community heuristic, not a CYC standard.

Wraps per inchUsual category
18+Lace
14–18Fingering / Super Fine
12–14Sport / Fine
11–12DK / Light
9–11Worsted / Medium
7–9Bulky
5–7Super Bulky
5 or fewerJumbo

Why the category is only a starting point

Weight categories describe a range, not a guarantee. A loosely spun DK and a tight aran can both measure 20 stitches per 10 cm. Fibre, spin and ply change the fabric more than the label does.

Use the category to narrow your choice, then swatch. If you are substituting, calculate by length and match the gauge band rather than trusting the number on the band.

Eight yarn balls in a row, increasing in thickness from lace to jumbo
Eight categories, one shared gauge language.

Questions

My yarn sits between two categories. Which do I pick?

Pick the one that matches the gauge you actually want to knit. If your gauge lands on the boundary, the pattern's gauge and fabric goal should decide, not the label.

Does crochet use the same weight categories?

Yes, but the gauge figures differ because single crochet is denser than stockinette. Use the crochet column rather than converting from the knitting column.

Is WPI reliable?

It is useful for unlabelled stash yarn, but it depends on how tightly you wrap. Measure twice, and treat the result as a hint rather than a measurement.

Source: Craft Yarn Council, Standard Yarn Weight System and Wraps Per Inch.