Yarn Calculator

Yarn requirement is an area problem with a fudge factor, and it is honest to say so up front. There is no exact formula, because how much yarn a square foot of fabric takes depends on your hook or needle size, your tension, and the stitch you choose.

What does work is a lookup table. For each yarn weight class there is a typical yardage per square foot of medium-density knitted fabric, assembled from what published patterns actually call for. Worsted sits around 100 yards per square foot; super bulky around 42; fingering around 240.

From there it is two multipliers. Crochet consumes roughly 30% more than knitting for the same area, because crochet stitches are taller and each one wraps more yarn. And your stitch density shifts it again, open lace uses about 20% less, tight garter or single crochet about 25% more.

1. Step 1 Finished area area_sqft = width_in × length_in ÷ 144
2. Step 2 Base yardage for the yarn weight from the table, #1 = 240, #2 = 175, #3 = 135, #4 = 100, #5 = 65, #6 = 42 yd per sq ft
3. Step 3 Adjust for stitch and craft yd_per_sqft = base × density_factor × craft_factor Density, open 0.8, medium 1.0, dense 1.25. Crochet multiplies by 1.3.
4. Step 4 Total, with a margin total_yards = area × yd_per_sqft × 1.1 10% covers the swatch, the join-in tails and the edging you decide to add later.
5. Step 5 Convert to skeins skeins = ceil(total_yards ÷ yards_per_skein)

For example, a 50 × 60 in throw is 20.8 sq ft. In #4 worsted at medium density that is 100 yd per sq ft, so 2,083 yards knitted, 2,292 with the margin, which is 7 skeins of 364 yd. The same throw in crochet needs 2,979 yards, or 9 skeins.

• The yards-per-square-foot figures are rules of thumb derived from typical published pattern yardages, not laboratory measurements. Treat them as a shopping guide, not a specification.
• Crochet is modelled as using 30% more yarn than knitting for the same area. The real range is roughly 25–40% depending on stitch, double crochet is at the low end, single crochet at the high end.
• A 10% margin is added for swatching, tails woven in, and the border you decide to add halfway through. It does not cover a change of mind about size.
• Gauge is the single biggest variable and this calculator cannot see yours. Someone who works tightly can use 20% more yarn than someone loose, with the same yarn and pattern.
• Hats are modelled as a flat area of about 1.7 square feet, which matches typical adult beanie yardages. Heavily cabled or double-brimmed hats use considerably more.
• Colourwork is not modelled. Stranded knitting carries a second yarn across the back and can use 1.5 to 2 times the plain figure.
• Skein yardage is taken from your input. Ball bands sometimes state metres rather than yards, 100 m is 109 yd.