Yarn Weight Chart: Categories 0–7, Gauge & Needle Sizes

The yarn weight chart

The table below is the Craft Yarn Council standard yarn weight system, categories 0 to 7, with knit and crochet gauge over 4 inches, recommended needle and hook sizes, and wraps per inch (WPI). Knit gauge is counted in stockinette stitch over 4 inches (10 cm); crochet gauge is double crochet over 4 inches. WPI is how many times the strand wraps around a ruler in one inch — a quick way to identify an unlabeled skein. Print it and keep it by the stash.

Yarn weights 0–7 — the full Craft Yarn Council chart

How to read the chart: gauge, needles, and WPI

Start with the number on the ball band: the category inside the skein symbol, 0 to 7, is the most reliable thing on the label. Then read across the row. Category 4 Medium — worsted, afghan, aran — knits at 16–20 stitches per 4 inches on US 7–9 needles (4.5–5.5 mm) and crochets at 11–14 double crochet per 4 inches on an I-9 to K-10½ hook (5.5–6.5 mm). WPI, wraps per inch, is the fallback: wrap the strand snugly around a ruler without stretching it and count the wraps in one inch — 9–12 wraps is Medium, 14–30 is Super Fine, 5–6 is Super Bulky. When the label is missing, go by gauge; when the gauge is missing, go by the name; when all three are missing, swatch.

Looking it up backwards: gauge and needle size

Gauge 28 stitches per 4 in: 28 falls in the 27–32 range, so the yarn is Super Fine (1) — fingering, sock, baby — on US 1–3 needles.

Gauge 14 stitches per 4 in: 14 falls in the 12–15 range, so the yarn is Bulky (5) — chunky, craft, rug — on US 9–11 needles.

Gauge 8 stitches per 4 in: 8 falls in the 7–11 range, so the yarn is Super Bulky (6) — on US 11–17 needles.

Gauge 35 stitches per 4 in: 35 falls in the 33–40 range, so the yarn is Lace (0) — on US 000–1 needles.

Category 2: Fine (sport, baby) — 23–26 stitches per 4 in, needles US 3–5 (3.25–3.75 mm), crochet 16–20 dc, hook E-4 to 7.

Needle 3.5 mm: 3.5 mm falls in the 3.25–3.75 mm range, so the yarn is Fine (2) — 23–26 stitches per 4 in.

A gauge between two ranges rounds to the nearest range edge, and an exact tie goes to the finer range: a gauge of 26.5 sits exactly between 26 (Fine) and 27 (Super Fine), so the lookup returns Super Fine (1). One overlap to know about: Light is 21–24 and Fine is 23–26, so gauges of 23 and 24 match both — a yarn at 23 stitches could be either, and the ball band decides. Needle sizes share boundary values the same way: 2.25 mm is the top of Lace and the bottom of Super Fine.

Output · formula · meaning

Who uses this

• The pattern shopper: has a pattern calling for worsted weight and learns that is category 4 Medium — 16–20 stitches per 4 inches on US 7–9 needles — so any ball band with a 4 in the skein symbol will work, whatever the brand calls it.
• The stash sorter: finds an unlabeled skein, measures 28 stitches per 4 inches on a swatch, and learns it is Super Fine (1) — fingering, sock, baby — on US 1–3 needles, and that it belongs with the sock yarn, not the worsted.
• The substituter: wants to swap a DK for a sport weight and learns DK is category 3 Light at 21–24 stitches while sport is category 2 Fine at 23–26 — the ranges overlap at 23–24, so the swap can work, but only with a gauge swatch to prove it.
• The bulky blanket knitter: measures 8 stitches per 4 inches and learns the yarn is Super Bulky (6) — US 11–17 needles, 7–9 double crochet, hook M-13 to Q — and that a blanket in it will knit up in a weekend, not a month.

Accuracy & limitations

The gauge, needle, and hook ranges are the Craft Yarn Council standard, verified against the Council's published chart. Two details were corrected against the published sources while building this page: the Super Bulky crochet gauge is 7–9 double crochet per 4 inches, and the Jumbo WPI range is 1–4; the WPI column uses the ranges three published charts agree on (sarahmaker, TL Yarn Crafts, Sheep & Stitch). WPI is approximate and varies by fiber and spin — it is a supplementary measure, not part of the Council's published chart, so treat the WPI column as a guide for unlabeled skeins rather than a specification. Gauge ranges are the standard, but individual yarns vary — a light worsted and a true aran both sit in category 4 yet can knit up two or three stitches apart over 4 inches — so always swatch. Fiber matters too: a category 4 wool and a category 4 cotton should both knit at 16–20 stitches per 4 inches, but the fabrics feel nothing alike, and the drape, the yardage, and the care instructions all differ. UK and Australian patterns use ply names instead of numbers — 8-ply lands near category 3, 10-ply near category 4 — but ply counts strands, not thickness, so the number on the ball band is the safer guide.