For dogs and cats, if you feel over the pet's rib cage, it should feel no more padded than the back of the owner's hand. (See the Muscle Condition Score chart: Cats or Dogs) Your cat is overweight if he is 10% more than the ideal weight and obese if over 20% of the ideal weight.

How can you tell if your cat is getting fat?

Spine: Run your hands across your cat's back. Your cat is overweight if you can't easily feel bones below a layer of fat. Waist: Look at your cat from above. If you can't see their waist, or the space between their ribs and hips protrudes, that's a sign your cat is overweight.

Why is my cat gaining weight all of a sudden?

What causes weight gain in cats? Cat weight gain is the result of an increase in body fat. This is usually caused by eating too much, especially when combined with lack of exercise.