Knitting Calculators

Sweater Yarn Calculator

Use this sweater yarn calculator to estimate how much yarn you need for a knitted pullover, cardigan, or vest. Choose the size, yarn weight, and style, and get a realistic yardage and skein count based on standard garment requirements.

Last reviewed: June 2026

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From the ball band; default suits a typical worsted ball.

Your result will appear here after you press Calculate.

Yardage is a planning estimate based on standard sizing. Cables, colorwork, and extra ease can add 15–30%.

Formula used

The calculator starts from a standard yardage for the size, then adjusts:

  • Base yarn = standard yards for the chosen size (long-sleeve worsted pullover)
  • × yarn-weight factor (lighter yarns need more yards, heavier yarns fewer)
  • × style factor (vest, short sleeves, or cardigan)
  • × body-length factor (cropped or tunic)
  • Skeins = ceil(total yards ÷ yards per skein)

Worked examples

Adult medium worsted pullover

An adult M long-sleeve pullover in worsted yarn needs roughly 1,150 yards — about 6 skeins of 220-yard yarn.

Adult large fingering cardigan

An adult L cardigan in fingering-weight yarn needs roughly 2,100 yards because fine yarn covers less area per yard.

How to use this calculator

  1. Choose the size you're knitting for, from child sizes to adult 3XL.
  2. Select your yarn weight — lighter yarns need more total yardage.
  3. Pick the style (pullover, cardigan, or vest) and sleeve length.
  4. Press Calculate to see the estimated yardage and number of skeins.

Reference chart

Approximate yarn needed for an adult pullover (long sleeves)
SizeWorsted (yd)DK (yd)Fingering (yd)
XS9009901,350
S1,0001,1001,500
M1,1501,2651,725
L1,3001,4301,950
XL1,5001,6502,250
2XL1,7001,8702,550

Frequently asked questions

How much yarn do I need to knit a sweater?

A common range for an adult pullover is about 1,000–1,500 yards in worsted weight, more for larger sizes or finer yarns. This calculator gives a size-specific estimate based on standard garment requirements, then adjusts for yarn weight and style.

How many skeins of yarn for a sweater?

Divide the estimated yardage by the yards per skein on the ball band and round up. A worsted adult sweater often needs 5–7 standard skeins. Always buy one extra ball in the same dye lot to cover swatching, gauge changes, and seams.

Does yarn weight change how much I need?

Yes, significantly. Finer yarns (lace, fingering) cover less area per yard, so the same sweater needs more total yardage. Heavier yarns (bulky, super bulky) cover more area, so you need fewer yards. The calculator factors this in automatically.

How much extra yarn do cables and colorwork need?

Cables pull the fabric in and use roughly 15–30% more yarn than plain stockinette. Stranded colorwork carries yarn across the back and can use 20–40% more. Add a buffer and buy spare balls if your design is heavily textured.

Is the estimate for a pullover or a cardigan?

You can choose. A cardigan needs slightly more yarn than a pullover because of the button bands and front overlap, while a vest needs much less because it has no sleeves. Select the style that matches your pattern.

Should I buy yarn before or after swatching?

Swatch first to confirm your gauge, then buy. If your gauge differs from the pattern, your finished size — and therefore your yarn needs — will change. Once you're happy with the swatch, buy all the yarn at once from the same dye lot.