Cat Calorie Calculator NRC Method

UK Pet Food's cat calorie calculator is a free online tool to provide helpful guidelines on how much to feed your cat using the NRC method under FEDIAF guidelines. 


NRC 4-Step Method

Our online cat calorie calculator uses the Predictive Equations of NRC 2006 (the 4-step method) to estimate the Metabolisable Energy (ME) of prepared foods for cats and dogs in accordance with FEDIAF Guidelines. Please refer to these guidelines for more detail.

1. Calculate GE (Gross Energy)
2. Calculate energy digestibility (%)
3. Calculate digestible energy
4. Convert into metabolizable energy

Any analysis of cat food provided by the manufacturer will be the most accurate for that specific product. However, if the calorie content is not provided on the label or the website of the manufacturer for your cat's food, you can use this calculator for a good estimate of the energy content of the product.

Some brands of cat food have lower feeding amounts due to the formulation of their diets and different levels of digestibility. Please contact the manufacturer for the most accurate calorie content of their product and feeding guides.

For more information and how the formulas are used in this calculator please refer to our Calorie Fact Sheet.

You can use our cat calorie calculator as a starting point, however, each cat should be fed to their ideal weight and body condition score. You can use our Cat-Size-O-Meter to guide you on assessing your cat's size and weight.

Using this information as a starting point, each individual cat should . Regular weighing of the animal and adjusting their food to their need based on weight gain/loss, by a veterinary professional, is also critical. 

On this page, the term ‘calorie’ refers to kilocalorie unit of energy (symbol: kcal).

Cat Calorie Calculator

*We are aware of issues with the calculators not appearing on certain browsers and are working towards finding a solution to this. 

If you feed your cat treats and snacks, please note they should not form more than 10% of the whole diet’s calorie content. This means at least 90% of calorie contribution should come from the complete pet food, and up to 10% from treats.

Pet owners are advised to use accurate kitchen scales to weight the food to the exact amount recommended by the manufacturer or their vet. Feeding based on volume or estimating the amount of food is subject to error.