Free crochet tool
Yarn Substitution Calculator
Swap one yarn for another by comparing yardage per skein and total length needed.
Skeins of your new yarn
5
Exact: 4.71 skeins — consider one extra from the same dye lot
Total length needed
800 yd
732 m
Thickness check
Your new yarn has about 15% less length per gram, so it may be thicker. Swatch carefully.
Different fibers have different densities, so compare yarns of similar fiber for the most reliable result.
How to use it
- 1
Enter how many skeins the pattern calls for and the length of each.
- 2
Enter the length (and ideally the weight) of one skein of your new yarn.
- 3
Buy the recommended number of skeins from a single dye lot, and swatch before starting.
How it works
Total length = skeins × length per skein. New skeins = total length ÷ length of your new skein, rounded up. Always substitute by length, never by weight — different fibers weigh different amounts for the same length.
Comparing length per gram gives a rough thickness check between similar fibers. For more detail, read our yarn substitution guide.
Common questions
Can I substitute a yarn of a different weight?
You can, but the size and drape will change. Match the weight category and gauge for anything that needs to fit.