Our how big will my cat get calculator is created to estimate your kitten’s adult size based on various physical measurements and characteristics.
If you have a 4-month-old Maine Coon kitten weighing 5 pounds, the calculator would analyze this data along with breed-specific growth patterns to estimate an adult weight range of 15-25 pounds, as Maine Coons are typically larger cats.
How Big Will My Cat Get Calculator
| Kitten Details | Current Weight (lbs) | Age (Months) | Estimated Adult Weight (lbs) | Breed |
|---|---|---|---|---|
| 3mo Maine Coon | 2.0 | 3 | 15.0 | Maine Coon |
| 4mo Ragdoll | 3.5 | 4 | 20.0 | Ragdoll |
| 5mo Siamese | 4.0 | 5 | 8.0 | Siamese |
| 6mo Bengal | 6.0 | 6 | 12.0 | Bengal |
| 4mo British Shorthair | 3.0 | 4 | 10.0 | British Shorthair |
| 5mo Abyssinian | 3.5 | 5 | 9.0 | Abyssinian |
| 7mo Norwegian Forest Cat | 7.0 | 7 | 15.0 | Norwegian Forest Cat |
| 8mo Sphynx | 6.5 | 8 | 12.0 | Sphynx |
| 3mo Persian | 2.5 | 3 | 10.0 | Persian |
| 6mo Scottish Fold | 4.5 | 6 | 11.0 | Scottish Fold |
| 5mo Burmese | 3.8 | 5 | 9.5 | Burmese |
| 9mo Devon Rex | 5.2 | 9 | 10.5 | Devon Rex |
| 10mo Russian Blue | 7.0 | 10 | 12.0 | Russian Blue |
| 11mo Tonkinese | 6.0 | 11 | 11.5 | Tonkinese |
| 12mo Chartreux | 8.0 | 12 | 14.0 | Chartreux |
Kitten Size Chart By Month
Here’s a detailed growth table showing average kitten weights by month for common domestic cats:
| Age (Months) | Small Breeds (lbs) | Medium Breeds (lbs) | Large Breeds (lbs) |
|---|---|---|---|
| Birth | 0.1 – 0.2 | 0.1 – 0.2 | 0.1 – 0.2 |
| 1 | 0.5 – 0.8 | 0.6 – 0.9 | 0.7 – 1.0 |
| 2 | 1.2 – 1.8 | 1.4 – 2.0 | 1.6 – 2.2 |
| 3 | 2.0 – 2.8 | 2.2 – 3.0 | 2.5 – 3.5 |
| 4 | 2.8 – 3.8 | 3.0 – 4.2 | 3.5 – 5.0 |
| 5 | 3.5 – 4.5 | 4.0 – 5.2 | 4.5 – 6.5 |
| 6 | 4.0 – 5.0 | 4.8 – 6.0 | 5.5 – 7.5 |
How Big Will My Kitten Get Calculation Formula
The formula for estimating adult cat size is:
Adult Weight = (Current Weight ÷ Age in Months) × 12A more accurate formula considers Kitten’s breed factors:
Adult Weight = (Current Weight ÷ Age in Months) × 12 × Breed Factor- Small breeds: Breed Factor = 0.8
- Medium breeds: Breed Factor = 1.0
- Large breeds: Breed Factor = 1.2
For a 3-month-old medium-breed kitten weighing 2.5 pounds: (2.5 ÷ 3) × 12 × 1 = estimated adult weight of 10 pounds.
How to Calculate How Big Will My Cat Get?
To calculate your cat’s projected size:
- Record current measurements: Weight in pounds, Age in months, Breed type
- Apply the formula with the appropriate breed factor: Adult Weight = (Current Weight ÷ Age in Months) × 12 × Breed Factor
- Consider genetic factors: Parent sizes, Gender (males typically larger), Spaying/neutering status
A 4-month-old female Siamese kitten weighing 3.2 pounds: (3.2 ÷ 4) × 12 × 0.8 = estimated adult weight of 7.68 pounds.
How much bigger will a 6-month-old cat get?
At 6 months, cats have typically reached about 50-60% of their adult size. To estimate remaining growth:
- Calculate current percentage of adult size.
- Determine growth potential.
A 6-month-old cat weighing 6 pounds:
- Estimated adult weight: (6 ÷ 6) ×12 ×1 = estimated adult weight of 12 pounds.
- Current percentage: (6 ÷12) ×100 = current percentage of 50%.
- Expected additional growth: 6 more pounds.
At what age do cats reach full size?
Cats typically reach full size between 12-18 months, varying by breed:
- Small breeds: 12-14 months
- Medium breeds: 14-16 months
- Large breeds: 16-18 months
A Russian Blue (medium breed) typically:
- Reaches 90% of adult size by 12 months
- Fully matures by 15 months
- Final weight: 8-12 pounds
Can you tell how big a cat will get by its tail?
While tail length can be an indicator, the general rule is:
Tail Length Ratio = Tail Length ÷ Body Length- Long-tailed breeds: 0.7-0.9
- Medium-tailed breeds: 0.5-0.7
- Short-tailed breeds: 0.3-0.5
A kitten with a 6-inch tail and 8-inch body: 6 ÷8 = 0.75 (suggests long-tailed breed, potentially larger adult size).
Can you tell how big a kitten will be by its paws?
Paw size can indicate adult size through the Paw Ratio Method:
Paw Ratio = Paw Width × 4A kitten with a 0.75-inch paw width:
Calculation: 0.75 × 4 = 3 inches body width prediction (suggests medium-large adult size).
References:
- Cornell University College of Veterinary Medicine – “Feline Growth and Development”
- International Cat Care – “Cat Size and Growth Charts”
- American Veterinary Medical Association – “Feline Life Stages”
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