A PRACTICAL START
Start with the project
A warm sweater, a hard-wearing sock, and a light summer top place different demands on yarn. Begin with the garment, the climate, and how often you expect to wear it.
A PRACTICAL START
Read the label
Check fibre content, ball weight, length, care instructions, and the recommended needle range. Compare metres per 100 grams when you are comparing yarns of different weights.
A PRACTICAL START
Make a swatch
A small gauge swatch helps you see how your stitches behave after washing. Measure it only when it is dry and rested; adjust needle size or yarn choice if the fabric does not match the project.
A PRACTICAL START
Think about care
For a garment that will be washed often, care instructions matter as much as colour. Check whether the fibre needs hand washing, flat drying, or a gentler routine before you begin.
These are general starting points. Always follow the yarn label and the pattern designer’s instructions for your project.
A WORKED EXAMPLE · ILLUSTRATIVE LABELS
Compare the length you need, then check the fabric
Suppose a pattern calls for 900 metres. An imaginary Yarn A has 125 metres in a 50-gram ball: 900 ÷ 125 = 7.2, so you would need at least eight whole balls, giving 1,000 metres. An imaginary Yarn B has 240 metres in a 100-gram ball: 900 ÷ 240 = 3.75, so four whole balls give 960 metres. The ball counts differ even though the total lengths are close. Allow for your size, swatch, and the pattern’s own guidance before buying.
Length is only the first check. Two yarns in the same weight category are not automatically interchangeable. Compare fibre, care, and the washed fabric as well as the pattern gauge. The Craft Yarn Council’s FAQ explicitly cautions that its weight system is not an interchangeability chart.
What a gauge difference can do
For another illustrative calculation, a pattern gauge of 20 stitches per 10 cm makes a 100-stitch panel about 50 cm wide. If your washed swatch measures 22 stitches per 10 cm, the same 100 stitches make about 45.5 cm. That is a meaningful change before shaping or ease is considered. Re-swatch with an appropriate needle or yarn and compare the fabric you actually like; do not rely on the ball band alone.
For the standard weight categories and suggested gauge ranges, see the Craft Yarn Council’s Standard Yarn Weight System. Its ranges are guidelines; follow the gauge in your chosen pattern. The Council’s label guide lists the fibre, length, care, dye lot and suggested tools commonly shown on a yarn label.