Kitten growth calculator
Our calculator helps you assess whether your kitten is growing as expected. It compares the kitten's current weight with the expected weight based on age and expected adult weight. A positive deviation means the kitten is heavier than expected, while a negative deviation indicates it's lighter.
Kitten growth curve
Kittens grow extremely quickly in the first 6 months, typically reaching about 75% of their adult weight by 6 months (26 weeks). Growth then gradually slows, with the cat reaching full adult weight around 12 months for most breeds. Large breeds like Maine Coon may continue growing until 3-4 years.
Normal weight development
A newborn kitten typically weighs 85-115 grams and should double its birth weight within the first 1-2 weeks. At 4 weeks a kitten typically weighs 400-500 grams, at 8 weeks about 800g-1 kg, and at 12 weeks about 1.2-1.5 kg. Regular weighing is the best way to monitor kitten growth.
When should you be concerned?
If your kitten deviates more than 20% from expected weight, contact your vet. Signs of poor growth include lack of appetite, lethargy, diarrhea or vomiting. Kittens that don't gain weight for more than 2-3 days should be examined by a vet.