SkeinoteGuides
The parts of a substitution the calculator cannot decide for you, each with the makers’ own labels as evidence.
Same weight category, different fabric
Two yarns printed "worsted" can knit up nothing alike. What the category actually promises, what it leaves out, and how a swatch settles it.
Reading a yarn label, and why some makers print no weight number
Yardage, grams, fiber, and the category symbol: what each one is for, and what to do when one is missing from the maker's page.
From skeins to yards and back
How to turn a pattern's skein count into a total length, and a total length into skeins of something else, with the rounding shown.
Solids and prints of the same yarn can have different yardage
The same yarn, the same maker, the same weight, and a different number on the band. Why the line you pick changes the skein count, with two makers' labels as the evidence.
When the pattern's yarn is discontinued
What a discontinued record still tells you, and how to substitute from the figures that remain.