Dog & Cat Food Portion Calculator
Estimate maintenance calories for a healthy adult dog or cat, then use the kcal per cup on the food label to estimate a portion. Individual needs vary.
For healthy adult maintenance at normal activity. Growth, senior care, weight loss or gain, illness, pregnancy and nursing need an individual feeding plan.
Awaiting Data
Enter details for a healthy adult pet for a maintenance estimate. Cup portions require the food label.
Estimated Maintenance Energy
per day (24 hours)
Approximate Daily Portions
Uses the kcal/cup you enter. Includes all food energy; subtract other foods and treats before converting a remaining allowance into cups.
Keep fresh drinking water available. This tool does not prescribe a daily water volume.
Always consult your veterinarian before making significant changes to your pet's diet.
Understanding Pet Caloric Needs
This is a starting estimate for a healthy, fully grown dog or cat at an ideal body condition. Individual needs vary. Track food amounts, body weight and body condition with your veterinarian rather than treating the result as a fixed prescription.
The Science: RER vs. MER
- RER (Resting Energy Requirement): The basic number of calories your pet needs to maintain essential bodily functions (breathing, digestion) while at rest. Formula:
RER = 70 x (Body Weight in kg)^0.75 - MER (Maintenance Energy Requirement): For normal adult maintenance, this tool uses 1.6 (neutered dog), 1.8 (intact dog), 1.2 (neutered cat), or 1.4 (intact cat). It does not calculate growth or treatment diets.
Method: Merck Veterinary Manual — nutritional requirements. For body condition and feeding records, see the WSAVA nutrition toolkit. These organizations do not endorse this calculator. Method checked 6 September 2026.
Reading Your Pet Food Label
The result provided above is in kilocalories (kcal) per day. To translate this into actual food:
- Look at the back of your pet's food bag or can.
- Find the caloric density, usually listed as "kcal/cup" or "kcal/100g".
- Divide the calorie allowance for this food by its kcal per cup for an estimated portion. Do not enter kcal/kg or kcal/100g into the cup field.