How big do Cavalier King Charles Spaniels get? The tool below projects your own puppy’s adult weight from its current age and weight, plotted against the typical Cavalier King Charles Spaniel growth curve.
Estimates combine your puppy’s current trajectory with typical growth curves for this breed and size class. Individual dogs vary — nutrition, genetics and neuter timing all matter. For health concerns, ask your vet.
The Cavalier King Charles Spaniel is a toy-sized breed. Adult males typically weigh 13–18 lb (5.9–8.2 kg) and females 13–18 lb (5.9–8.2 kg). Most Cavalier King Charles Spaniels reach about half their adult weight around 3.2 months, hit 90% by roughly 6.7 months, and are fully grown near 9 months. Toy breeds finish growing fastest of all dogs — most of their gain happens before six months.
When do Cavalier King Charles Spaniels stop growing?
Most Cavalier King Charles Spaniels reach their full adult height and weight by about 9 months. Growth is fastest before 3.2 months, then slows steadily — by 6.7 months your puppy will be about 90% of its final size.
How much should a Cavalier King Charles Spaniel puppy weigh at 4 months?
A typical 4-month-old Cavalier King Charles Spaniel weighs roughly 8–12 lb, about 64% of its adult weight. Use the calculator above with your puppy’s exact weight for a personalized estimate — individual dogs vary.