Cat Calorie Calculator

What this does

So you want a rough idea of how many calories your cat needs. This works it out. Enter your cat's weight, pick the condition that fits, and it gives you two figures, a resting energy number and a daily maintenance number. It starts with the same resting energy formula commonly used in veterinary nutrition, then applies the activity or life-stage factor selected in the tool. These factors are broad estimates, and real feeding needs can vary a lot from cat to cat.

How to use it

1. Enter your cat's weight, and pick the unit.
2. Choose the condition, such as neutered adult, kitten, or weight loss.
3. Pick the result unit, then tap Calculate to see the resting and maintenance energy.

Kilocalories, often just called calories, is the unit you will see on cat food, so that is the one to use.

How it works

It works the way vets do, in two steps. First it finds the resting energy requirement, the calories a cat burns just resting. That uses a well established formula:

resting energy = 70 × (weight in kg)^0.75

The power of 0.75 is there because metabolism does not scale in a straight line with body size. Then it multiplies that by a factor for your cat's condition to get the daily maintenance figure:

maintenance energy = resting energy × factor

This tool uses broad factors such as 1.6 for a neutered adult, 1.8 for an intact adult, 2.0 for a growing cat, 3.0 for a young kitten, 1.7 for weight gain, and 1.0 for weight loss. Different veterinary references may use different multipliers, so treat the result as a starting point, not a feeding prescription.

The two numbers it gives

You get resting energy and maintenance energy, and it helps to know the difference. Resting energy is the bare minimum a cat burns at rest, doing nothing. Maintenance energy is the realistic daily total, since it adds the factor for activity and life stage on top. For everyday feeding, the maintenance number is the one to work from. The resting number is mainly useful as the lower anchor, for instance as a reference point when a vet is planning careful weight loss.

Treat it as a starting point

To be straight about it, and vets agree, these formulas are a starting point rather than an exact figure. Two cats of the same weight can need different amounts to stay trim, depending on metabolism and lifestyle. So use the maintenance number to set an initial portion, then keep an eye on your cat over a few weeks and adjust. Cats are prone to putting on weight, especially indoor neutered ones, so if the waistline is creeping, ease back, and loop in your vet for any real weight loss plan.

Questions people ask

References

1. Merck Veterinary Manual. Nutritional Requirements of Small Animals. https://www.merckvetmanual.com/management-and-nutrition/nutrition-small-animals/nutritional-requirements-of-small-animals