🐾 Pets
Pet Food Serving Converter
Turn a feeding chart into the units on your own scoop: calories, grams, ounces, cups and cans. Add your pet's weight and life stage for a daily energy estimate. Press Convert.
About the pet food serving converter
Feeding guides are printed in whatever unit suited the manufacturer — cups on American dry food, grams on European labels, cans on wet food — and none of them match the scoop in your cupboard. This converter moves freely between calories, grams, ounces, cups and cans once it knows two things: the food's energy density and the weight of a cup or a can of it.
The optional panel below the result estimates daily energy from body weight using the standard veterinary formulas, then converts that into grams, cups or cans of the food you are feeding.
The formulas used
- Resting energy requirement: RER = 70 × (body weight in kg)0.75
- Maintenance energy requirement: MER = RER × life-stage factor
- Grams per day = MER ÷ kcal per gram of food
Life-stage factors
| Pet | Factor |
|---|---|
| Intact adult dog | 1.8 × RER |
| Neutered adult dog | 1.6 × RER |
| Inactive or overweight-prone dog | 1.2 – 1.4 × RER |
| Puppy under 4 months | 3.0 × RER |
| Puppy over 4 months | 2.0 × RER |
| Intact adult cat | 1.4 × RER |
| Neutered adult cat | 1.2 × RER |
| Kitten | 2.5 × RER |
What foods contain
| Food type | Energy density |
|---|---|
| Dry dog food | 330 – 400 kcal per 100 g |
| Dry cat food | 380 – 440 kcal per 100 g |
| Wet dog food | 80 – 120 kcal per 100 g |
| Wet cat food | 70 – 100 kcal per 100 g |
| Typical dry cup | about 100 g, so 350 – 450 kcal |
| Typical 400 g can | 320 – 480 kcal |
Worked examples
- A 20 kg neutered dog has an RER of 70 × 200.75 = 662 kcal, and a maintenance need of 662 × 1.6 = 1,059 kcal per day.
- At 360 kcal per 100 g that is 1,059 ÷ 3.6 = 294 g of dry food, or about 2.9 cups of 100 g each.
- The same dog fed a 400 g can at 420 kcal would need 1,059 ÷ 420 = 2.5 cans a day.
- A 4 kg neutered cat needs 70 × 40.75 = 198 kcal, times 1.2 = 237 kcal per day — roughly 60 g of dry food.
Frequently asked questions
Common mistakes to avoid
- Feeding the bag's suggested amount for an inactive dog. Bag guides are generous and assume an active adult.
- Switching foods without recalculating. A 360 kcal/100 g food and a 420 kcal/100 g food need different scoop sizes.
- Judging by volume alone. Cups of different kibble hold different weights.
- Weighing a growing puppy once. Puppy energy needs change quickly with age.
Sources and standards
A serving size on a pet food label is a starting point, not a prescription: it assumes a typical adult animal and a stated calorie density. AAFCO sets the labelling convention, and the page explains why body condition is a better guide than the number on the bag.
- Association of American Feed Control Officials
- US Food and Drug Administration — How to understand the Nutrition Facts label
Related tools
A note on pet feeding
These figures are general guidance based on typical energy densities and body-weight ranges. Individual needs vary with age, activity, neutering status and health, so confirm any change of portion or diet with your veterinarian.