Daily calories and grams per meal for dogs and cats, with separate maths for each: cats are dosed on ideal weight with a fixed safety floor, dogs on current weight scaled by activity. Targets adjust from your weekly weigh-ins.
Hi Product Hunt! Most feeding calculators run dogs and cats through one formula with a tweaked number. The two species actually need structurally different maths.
Both start from resting energy, RER = 70 x kg^0.75. A cat on a diet is then dosed on its ideal weight at a flat 0.80 x RER. Cutting a cat's calories too fast risks hepatic lipidosis, so the dose deliberately ignores activity and neuter status. A dog is dosed on its current weight, scaled by activity, with a lower floor.
The same numbers on paper (6.0 kg, body condition 7/9, neutered, moderately active, losing weight) come out at 187 kcal a day for a cat and 228 for a dog.
Enter a food's calories per 100 g and the app gives you grams for the meal, and the target adjusts week to week from real weigh-ins. The maths follows AAHA and WSAVA guidance; if you're a vet and something looks off, I want to hear it.