Shrinkage is not determined by fiber name alone
Textile dimensional change depends on construction and processing as well as laundering conditions. Two cotton garments, for example, can behave differently because their fabrics and finishes are different.
Respect temperature and drying limits
Stay within the garment care label for wash temperature and drying. Repeated high heat or mechanical action can be a poor choice for fit-sensitive items when the label specifies a lower-heat or non-tumble method.
Handle wool and knitwear carefully
Wool can felt or distort under unsuitable combinations of moisture, heat and agitation. Washable wool should be cleaned only by the method allowed on its label, and shape-sensitive knitwear may need flat drying.
Check fit before repeating a harsh process
If an item is especially fit-sensitive, inspect it after laundering and before repeated high-heat drying. A generic fiber profile cannot guarantee dimensional stability for a finished garment.
Garment care labels, appliance manuals and laundry-product directions can be more specific than a general guide. Use them when they set a tighter limit.