Yarn Yardage Estimator for Knitting Projects

Knitting patterns always list a yarn amount in yards or meters, but those numbers apply to a specific yarn weight and needle size.
If you are substituting a different weight, or scaling a pattern to a different size, you need to recalculate.

This calculator estimates how many yards you need for common project types.
The baseline figures come from averaging hundreds of finished-object posts and published pattern requirements, then adjusting by yarn weight and size.
They are solid starting points, not guarantees. Your personal tension and the pattern structure both affect how much yarn each stitch consumes.

Base yardage assumes worsted weight (roughly 200 yards per 100g skein).
Finer yarn - DK, sport, fingering - has more yards packed into each gram, but each stitch also covers less area, so you end up needing more total yards for the same project.
Bulky and super bulky yarn is the opposite: each stitch covers fabric quickly, and you need far fewer yards.

How much more, exactly

The multiplier is smaller than most knitters assume, and getting it wrong is expensive in both directions. These are the ratios this calculator uses, taken from published per-size sweater yardage:

One step finer is only about 15% more yarn, not the 30% that gets repeated on forums. Worsted all the way down to fingering is roughly one and a half times, not double. Lace weight sits off the bottom of this table and is the one case where you should ignore any generic estimate and trust the pattern.

For sweaters specifically, the sweater yardage calculator is the better tool. It carries a published figure for every size and weight pair rather than scaling one number, and it handles cardigans, short sleeves and cabled or stranded fabric. The two pages agree to within a few percent, which is as close as two yardage estimates have any business being.

For wearable projects like sweaters, always add 15-20% to the estimate.
Dye lots matter. If you run short and the store is out of your lot, the next skein will be slightly different, and it shows after blocking.
Buying an extra skein and returning it costs nothing. Ripping out a finished sleeve does.

For colorwork or cables, add another 10-20% on top of whatever this calculator gives you.
Cables pull in the fabric horizontally; carrying floats in colorwork adds bulk.
Both eat yarn faster than plain stockinette, and patterns notoriously underestimate the extra amount.

For hats, socks, and mittens, the estimate is fairly reliable since those items are standardized.
For sweaters and blankets, treat the number as a floor, not a ceiling.

The sock number is worth a sanity check against the thing every sock knitter already knows: one 100g skein of fingering weight, which is about 400 yards, makes one pair of adult socks with a little left over. If a yardage estimate tells you to buy three skeins for a pair of plain socks, the estimate is wrong, not your yarn.