Cat Size Calculator: Is Your Cat Small, Medium, or Large?
Estimate your cat’s size category by entering their breed, weight, and frame type below.
Understanding Cat Size Categories
Cats, like people, come in a wide range of sizes — from tiny 2 kg Singapuras to 10+ kg Maine Coons. Size depends on genetics, breed standards, frame, and weight. Knowing your cat’s expected size range can help you monitor growth, manage nutrition, and avoid obesity or underdevelopment. This calculator provides an estimate based on breed and skeletal build.
Standard Cat Size Ranges by Breed
| Breed | Expected Adult Size (kg) | Category |
|---|---|---|
| Singapura | 2.0–3.0 | Small |
| Siamese | 3.0–5.0 | Small to Medium |
| Persian | 3.5–6.0 | Medium |
| Domestic Shorthair | 3.0–6.0 | Medium |
| Ragdoll | 5.0–9.0 | Large |
| Maine Coon | 6.0–11.0+ | Large to Giant |
Frame Type Considerations
Two cats with the same weight may fall into different size categories if their bone structure varies. Use this rough guideline:
- Small frame: Fine bones, narrow chest, lighter muscles
- Average frame: Balanced build
- Large frame: Broad head, thick limbs, stocky body
How to Measure Cat Weight Properly
- Use a digital scale with at least 0.1 kg precision
- Weigh yourself, then weigh again while holding your cat
- Subtract the difference to get your cat’s weight
- Weigh at the same time of day for consistency
Cat Size Categories
- Small (under 3.5 kg): Typically includes breeds like Singapura, Cornish Rex, and Siamese
- Medium (3.5–5.5 kg): Domestic cats, Bengals, Persians, most housecats
- Large (5.5–8.0 kg): Ragdolls, Birmans, British Shorthairs
- Giant (8.0+ kg): Maine Coons, Norwegian Forest Cats, large mixed breeds
How Breed Affects Growth
Some breeds reach full size by 1 year, while others like Maine Coons grow until 3–4 years of age. Size also depends on sex (males are typically 15–30% heavier than females) and whether the cat is neutered early.
Size vs Health
A cat’s size alone does not indicate good or bad health. Instead, body condition score (BCS) and muscle tone are better indicators. An oversized cat can be healthy if muscular, just as a small cat can be unhealthy if underweight.
Frequently Asked Questions
What if my cat’s size is above or below its breed average?
Outliers exist. Mixed ancestry, nutrition in kittenhood, and hormonal changes (like early spaying) can affect final size. As long as body condition is ideal, size alone isn’t a concern.
Can I increase my cat’s size?
You can’t change genetics, but you can support healthy growth with high-quality kitten food, adequate play, and proper vet care. Avoid overfeeding, which adds fat, not bone or muscle.
Is size related to lifespan?
In general, smaller cats live slightly longer than larger breeds. However, health, lifestyle, and genetics play bigger roles in longevity than weight or height alone.
Should I choose a breed based on size?
Size is just one factor. Consider temperament, grooming needs, and activity level. Larger cats often need more space, stronger carriers, and heavier litter boxes — worth considering if space is limited.
Do cats stop growing after 1 year?
Most do, but large breeds like Maine Coons can grow for 3–4 years. Kitten food should usually be stopped at 12–18 months unless directed otherwise by a vet.
Conclusion
The Cat Size Calculator offers a simple way to estimate your feline’s build using breed, weight, and frame size. While not a substitute for veterinary evaluation, it helps owners better understand their cat’s development and adjust feeding or lifestyle accordingly. Whether your cat is compact or colossal, the most important factor is that they’re loved, active, and well cared for.