How it works
The pattern’s quantity is turned into metres first: balls × metres per ball, grams × metres per gram, or yards × 0.9144. Then it’s divided by the metres in one ball of your yarn and rounded up. With several colours, each colour is rounded up on its own, because you can’t share part of a ball between colours.
Is it a good swap?
Two yarns sold as DK can hold anything from 200m to 330m per 100g, as our guide to substituting yarn shows. The calculator compares metres per 100g: within about 10% usually means a similar thickness. A bigger gap means the fabric, the finished size and the yarn needed will all change, so crochet a swatch and compare it with the pattern’s tension before you buy everything. Fibre matters too: cotton is heavier and less stretchy than acrylic of the same thickness.
Example
Attic24’s Cosy Stripe asks for 15 balls of Stylecraft Special DK, 4,425m. In Paintbox Yarns Simply DK, at 276m a ball, that’s 17 balls, but each of the 15 colours has to be rounded up separately, so check the shopping list per colour in our yarn shopping planner. More options in alternatives to Special DK.