The swatch method
The most reliable way to know how much yarn a project needs is to weigh your gauge swatch. It is knitted or crocheted with your yarn, your hook or needles and your tension, so it accounts for stitch pattern, yarn thickness and how tightly you work.
The calculation
Yarn weight = project area ÷ swatch area × swatch weight × (1 + extra)
Skeins = yarn weight ÷ skein weight, rounded up
Yarn length = yarn weight ÷ skein weight × skein length
The calculator works for rectangular pieces: scarves, blankets, wraps, cushion covers and garment panels. For a sweater, add the front, back and sleeves as separate rectangles, or use the number of identical pieces for panels of the same size.
Example
A scarf 8 × 60 in in a pattern where a 4 × 4 in swatch weighs 6 g:
- area ratio: 480 ÷ 16 = 30 swatches;
- yarn: 30 × 6 = 180 g, plus 10% extra: 198 g;
- with 100 g skeins of 200 yd: 2 skeins, about 396 yd.
Typical yardage
| Project | Worsted weight yarn |
|---|---|
| Hat | 150 to 250 yd |
| Scarf | 300 to 500 yd |
| Baby blanket | 900 to 1,200 yd |
| Adult sweater | 1,000 to 1,500 yd |
| Throw blanket | 1,500 to 2,500 yd |
Thinner yarn and more textured stitches use more length; cables can use 20% to 30% more yarn than stockinette for the same area. Crochet generally uses about a third more yarn than knitting.
Tips
- Make a swatch of at least 4 × 4 in (10 × 10 cm), wash and block it as you will the finished piece, then weigh it on a kitchen scale accurate to 0.1 g or 1 g.
- Weigh a larger swatch for better accuracy if your scale reads only whole grams.
- Buy all skeins from the same dye lot: colors vary between lots.
- Add extra for fringe, tassels, seaming and pompoms.
- Keep the ball band: it gives the fiber, weight, length and care instructions.
Yarn weights
From thinnest to thickest, the Craft Yarn Council categories run from lace (0) through fingering (1), sport (2), DK (3), worsted (4) and bulky (5) to super bulky (6) and jumbo (7). Substituting a yarn of a different weight changes the gauge and the amount needed, so always swatch again.