Kitten weight calculator
Enter your kitten’s sex, age in weeks and weight. The calculator places the weight on the growth chart of healthy domestic shorthair kittens from 8 to 78 weeks and tells you whether it sits inside the typical range for that age. It is a guide, not a diagnosis.
Check your kitten’s weight
Result
Female, 17 weeks, 4.5 lb
Middle half, above the median
Between the median and the 75th centile.
- Typical range at this age
- 3.3–5.3 lb (1.51–2.40 kg)Median 4.3 lb (1.94 kg)
A weight outside the typical range is not a diagnosis. Weigh again on the same scale in a few days, and if it stays there or you are unsure, show the weights to your vet. Body condition matters as much as the number: WSAVA body condition chart for cats (opens in a new tab).
Everything is calculated in your browser; nothing is sent anywhere.
Where the numbers come from
The calculator uses the same lines as our kitten weight chart: our fit of the open Waltham data (Salt and colleagues, PLOS ONE, 2022), healthy intact domestic shorthair kittens from US clinics and a research colony, with separate lines for males and females.
What the result means
The result names the band your kitten’s weight falls in: below the typical range, inside it (split at the 25th centile, the median and the 75th), or above it. The typical range holds 82 of 100 healthy kittens of that age.
One weight is a snapshot. What tells you more is whether your kitten keeps to its band from one weigh-in to the next.
What it cannot tell you
Weight alone does not show body condition. If the weight is outside the typical range, check the number and weigh again in two weeks; if it stays there, or you are worried, ask your vet.
Frequently asked questions
Does it work for purebred cats?
It is built on domestic shorthair kittens. Breeds that grow larger or for longer, such as the Maine Coon, may sit above the bands without anything being wrong.
My kitten was neutered. Can I still use it?
Yes, as a rough guide. The data come from kittens weighed before neutering, and weight often rises faster afterwards, so a neutered kitten may drift upward on the chart.
Why does it start at 8 weeks?
There were too few weighings of younger kittens in the data, so the charts start at 8 weeks.
Sources
- Salt C, German AJ, Henzel KS, Butterwick RF. PLOS ONE. Growth standard charts for monitoring bodyweight in intact domestic shorthair kittens from the USA. 2022. doi.org (opens in a new tab) (accessed )
- University of Liverpool Research Data Catalogue. Growth standard charts for monitoring bodyweight in Domestic Shorthair kittens: supporting data. 2021. doi.org (opens in a new tab) (accessed )
- WALTHAM Petcare Science Institute. WALTHAM Kitten Growth Charts. waltham.com (opens in a new tab) (accessed )
- WSAVA Global Nutrition Committee. Body Condition Score: cat. wsava.org (opens in a new tab) (accessed )