CatCareHub
Free Tool

Cat Calorie Calculator

Daily calorie needs for maintenance, loss or gain.

How many calories does your cat need a day? It depends on weight, age, activity and whether they're neutered. This tool uses the standard veterinary RER formula (70 × kg0.75) plus a life-stage factor to estimate daily calories for maintaining, losing or gaining weight.

Cat Calorie Calculator

Enter weight, life stage, activity and neuter status, then calculate.

How the cat calorie calculator works

Vets start from the Resting Energy Requirement (RER) — the calories a cat burns at rest — calculated as 70 × (body weight in kg)0.75. The daily Maintenance Energy Requirement (MER) is then RER multiplied by a factor for life stage, neuter status and activity: neutered adults use about 1.2, intact adults about 1.4, and growing kittens up to 2.5.

For weight management, the calculator shows a lower figure for gradual loss and a higher one for gain, so you can pick a target with your vet.

How to use it

  1. Enter weight and unit. Add your cat's current weight in kilograms or pounds.
  2. Set the details. Choose life stage, activity level and whether your cat is neutered.
  3. Calculate. See daily calories to maintain, lose or gain weight, plus the resting (RER) figure.

Key takeaways

  • RER = 70 × kg^0.75; daily need = RER × a life-stage and activity factor.
  • Neutered adults use a ~1.2 factor; kittens up to ~2.5.
  • Aim for slow weight loss of about 0.5–1% of body weight per week.

Frequently asked questions

How many calories does an average cat need?
A typical 4–4.5 kg (9–10 lb) neutered indoor adult needs roughly 200–250 kcal per day, but the exact figure depends on activity and body condition — use the calculator for a personalised estimate.
What formula is used to calculate cat calories?
Resting Energy Requirement (RER) = 70 × (body weight in kg)^0.75. Daily maintenance energy is RER multiplied by a factor for life stage, neuter status and activity.
Do neutered cats need fewer calories?
Yes. Neutering lowers metabolic rate, so neutered cats generally need fewer calories than intact cats of the same weight — which is why the calculator adjusts for it.
How do I help my cat lose weight safely?
Feed around the 'weight loss' figure, add play, and aim for no more than 0.5–1% of body weight per week. Always confirm a plan with your vet first.