Use this for a label, not a calorie prescription

This tool calculates the calories in a weighed serving from the calorie information on that food's label. It does not estimate daily needs from weight, breed, age or activity. Establish an appropriate diet and allowance separately with your veterinary team; Cornell's feeding guidance explains why nutritional suitability matters [1].

Match the two label inputs

Enter a calorie value and the gram weight that value describes. Then enter the grams you plan to serve. Use values from the same product and the same label basis.

  • Per 100 g: enter the stated kcal and 100 grams.
  • Per kilogram: enter the stated kcal and 1000 grams.
  • Per can: use kcal for the whole can and its net weight in grams.

If the label only states calories per cup and gives no reliable gram equivalent, do not guess the cup weight. Ask the manufacturer for a gram-based value. Use kcal, not an unconverted kJ number.

Work through two examples

Hypothetical dry food: 360 kcal per 100 g and a 35 g serving gives 360 ÷ 100 × 35 = 126 kcal.

Hypothetical wet food: 90 kcal per 85 g can and a 42.5 g serving gives 90 ÷ 85 × 42.5 = 45 kcal. Those example portions together contain 171 kcal. This total is not a recommended ration for any cat.

Common entry errors

Entering 100 instead of 1000 grams for a per-kilogram label makes the result ten times too large. Entering an entire can's calories alongside half a can's weight doubles the apparent energy density. Using one food's label for a different product gives an unsupported result even when the arithmetic is correct.

Weigh the serving with a tared bowl. Run each food separately for mixed feeding and record the actual products. See feeding basics for organizing portions and extras.

Keep the scope clear

The form validates positive numeric values and returns a rounded arithmetic result; it cannot verify that the label was copied correctly or that the portion suits your cat. Inputs are calculated locally and are not stored in your private profile. Appetite changes need veterinary advice, not a different conversion [2].