Swapping to a different yarn? Find out exactly how many skeins you'll need.
The safest way to swap yarns is to match total length, not skein count or weight. A pattern written for 5 skeins of a 200m yarn actually needs 1,000 meters of yarn — so if your substitute only has 160m per skein, you'll need more skeins to reach that same 1,000m, even though the skein count looks different. This calculator does that conversion for you, and adds a cost estimate if you enter a price.
Should I match yarn by weight or by length when substituting?
Match by length (yardage/meters), not weight. Length determines how much fabric a yarn produces, while weight varies a lot between fibers — a wool skein and an acrylic skein of the same weight can have very different lengths.
Do I need to check gauge when substituting yarn?
Yes, always swatch with the substitute yarn and hook before starting. Even yarns of the same weight category can behave differently, so check your gauge with the Gauge Calculator before committing.
What if the substitute yarn is a different weight category?
You will likely need a different hook size and your finished project will drape differently. It is best to substitute within the same yarn weight category when possible — see the Yarn Weight Chart for equivalents.