What is the ideal weight for a Siamese cat?

Adult Siamese cats typically weigh 2.5–4.5 kg (5.5–10 lb), with males generally heavier than females. Rather than a single target number, the ideal weight for a specific cat is best assessed using the WSAVA body condition score — a BCS of 4–5 out of 9 indicates ideal condition for most Siamese.

My Siamese feels very bony — is that normal?

Siamese cats have a naturally slim, angular build with less fat covering than heavier breeds, so feeling ribs with gentle pressure is normal and expected in a healthy Siamese at BCS 4–5. However, if the ribs are sharp with no fat covering at all, or if there is visible muscle wasting, the cat may be underweight and a vet assessment is warranted.

Can Siamese cats become overweight?

Yes — particularly after spaying or neutering, or as they age and become less active. Siamese cats are less obesity-prone than some breeds, but weight gain does happen and can be easy to miss on their slim frame. Checking body condition every few months is the best way to catch it early.

Siamese Ideal Weight Guide | PetCalculator

Siamese cats have a distinctive slim, tubular build — here's how to interpret their healthy weight range, read their body condition, and spot the difference between lean and underweight.