About Cat Calorie Calculator

What this site does

Cat Calorie Calculator estimates how many calories a cat needs each day. You enter weight, age, activity, body condition, and spay or neuter status. The tool then shows daily calories, a practical range, and, if you add the food’s calorie count, how much to feed.

The site has one job: to make a common feeding question easier to answer. It does not list, rank, or promote any pet food brand.

Who it is for

Cat owners, caregivers, foster carers, breeders, and anyone who wants to understand feline feeding. If your cat has a health condition, use the result as a talking point with your vet.

How the calculator works

The tool uses two steps that are common in veterinary nutrition.

1. Resting Energy Requirement (RER). RER = 70 × weight in kg, raised to the power of 0.75.
2. A factor for your cat. The factor depends on growth stage, activity, spay or neuter status, and any weight goal.

The formula section on the tool page lists every factor and rounding rule, so you can check the math yourself.

Our commitment to accuracy

• We show the formula, the factors, and the rounding rules instead of hiding them.
• We label results as estimates, with a practical range of 10% above and below.
• We test the calculation code with automated cases that cover normal, boundary, and invalid inputs.
• We add safety notes where they matter, such as weight loss pace and the need for a vet when a cat is too thin.

No calculator can know your cat’s metabolism, health, or food in full. Weigh your cat regularly and adjust with your vet.

Our commitment to privacy

All calculations happen in your browser. We do not receive your cat’s weight, age, or food details. We do not run advertising or analytics. Read the Privacy Policy and the Cookies Policy for the full list of what is stored and where.

Corrections and feedback

If you think a number, factor, or sentence is wrong, please tell us. Write to support@readway.site or use the contact page. Include the page, what you saw, and what you expected. We check each report against published veterinary references. When we confirm an error, we fix it and update the “last updated” date on the affected page.