Why use a swatch?
Charts that give one figure per yarn weight can be far off, because the yarn a piece uses depends on the stitch pattern, your needle or hook size and your tension — and crochet usually uses noticeably more yarn than knitting for the same area. A swatch made in your actual yarn and stitch captures all of that.
Yarn needed = yarn in swatch × (project area ÷ swatch area) × (1 + extra)
Skeins = yarn needed ÷ yarn per skein, rounded up
Skeins = yarn needed ÷ yarn per skein, rounded up
Example: a 6 × 6 in swatch (36 sq in) that uses 10 g of yarn. A 50 × 60 in throw is 3,000 sq in, or 83 swatches, so it needs about 833 g — 917 g with 10% for a border and joining. In 100 g skeins, that is 10 skeins.
Standard blanket sizes
| Blanket | Inches | Centimetres | Area |
|---|---|---|---|
| Preemie | 13 × 15 | 33 × 38 | 195 sq in |
| Newborn (largest) | 36 × 36 | 91 × 91 | 1,296 sq in |
| Stroller | 30 × 35 | 76 × 89 | 1,050 sq in |
| Crib | 45 × 60 | 114 × 152 | 2,700 sq in |
| Lapghan | 36 × 48 | 91 × 122 | 1,728 sq in |
| Throw | 50 × 60 | 127 × 152 | 3,000 sq in |
| Twin | 60 × 80 | 152 × 203 | 4,800 sq in |
| Full | 80 × 90 | 203 × 229 | 7,200 sq in |
| Queen | 90 × 100 | 229 × 254 | 9,000 sq in |
| King | 108 × 100 | 274 × 254 | 10,800 sq in |
Sizes from Mary Maxim’s blanket size chart. There is no single standard; mattress sizes, overhang and personal preference all change the numbers.
Weighing a swatch
- Weigh the ball before you start the swatch, on a scale that reads to 1 g.
- Make the swatch in the project’s stitch pattern, at least 6 × 6 in (15 × 15 cm), and block it.
- Weigh the ball again. The difference is the yarn in the swatch. (Or unravel the swatch and measure its length.)
- Buy from one dye lot and add a skein for safety — matching a dye lot later is often impossible.
Last reviewed: 2026-10-04 · Disclaimer