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Yarn calculator: how much yarn do I need?

Estimate yardage and skeins from a swatch, or get a typical range for hats, scarves, sweaters and blankets.

Units

Swatch width

Swatch height

Swatch weight (g)

Length per ball

Weight per ball (g)

Project piece width

Piece length

Number of pieces

For a sweater, add the front, back and two sleeves as rectangles (sleeves: average width × length).

Add 10% for swatching, seams and weaving in

How the swatch method works

Your swatch tells you how many grams of yarn one square inch (or centimetre) of fabric uses. Multiply by the project’s area to get the total weight, then convert to length with the ball band: length = weight × (ball length ÷ ball weight).

Typical amounts are rough ranges for plain stockinette or single crochet. Textured stitches, cables and long or oversized fits can use 20–40% more.

How to use it

For the most accurate result, knit or crochet a swatch in your yarn and stitch, wash it, measure it and weigh it on a kitchen scale.
Enter the swatch size and weight, the yarn label’s length and weight per ball, and the area of your project.
No swatch? Use the typical amounts tab for a quick estimate by project and yarn weight.
Buy the number of balls shown, and one extra from the same dye lot if you can.

Questions

How much yarn do I need for a sweater?

An adult medium sweater typically takes around 900–1,200 yards of worsted weight yarn, 1,100–1,400 yards of DK or 1,400–1,800 yards of fingering. Larger sizes, long lengths, cables and crochet all use more.

Does crochet use more yarn than knitting?

Yes, usually about a quarter to a third more for the same area, depending on the stitch. This calculator adds 25% for crochet in the typical amounts tab.

Why weigh a swatch?

Weight tells you exactly how much yarn your stitch, tension and yarn use per square inch, so the estimate reflects your own knitting or crochet.