Pet Food Calculator Formula
Understand the math behind the pet food calculator. Each variable explained with a worked example.
Formulas Used
Daily Food Amount
daily_cups = adjusted_calories / 400Daily Calorie Need
daily_calories = adjusted_caloriesMonthly Food Cost
monthly_cost = adjusted_calories / 400 * 0.25 * 30 * food_cost_per_lbVariables
| Variable | Description | Default |
|---|---|---|
pet_weight_lbs | Pet Weight(lbs) | 40 |
activity_level | Activity Level (1=low, 2=mod, 3=high) | 2 |
food_cost_per_lb | Food Cost per Pound(USD/lb) | 3 |
base_calories | Derived value= 30 * pet_weight_lbs / 2.205 + 70 | calculated |
adjusted_calories | Derived value= base_calories * (0.8 + activity_level * 0.3) | calculated |
How It Works
Pet Food Calculation
Feeding amounts depend on your pet's weight, age, and activity level. The resting energy requirement (RER) formula provides a starting point.
Formula
RER (kcal/day) = 30 x Weight(kg) + 70
Daily Calories = RER x Activity Multiplier
Activity multipliers: Inactive/senior (1.1x), Moderate (1.4x), Active (1.7x). One cup of dry dog food averages about 400 calories. Always adjust based on body condition.
Worked Example
A 40 lb moderately active dog eating $3/lb food.
pet_weight_lbs = 40activity_level = 2food_cost_per_lb = 3
- 01Weight in kg = 40 / 2.205 = 18.14 kg
- 02RER = 30 x 18.14 + 70 = 614 kcal
- 03Adjusted = 614 x 1.4 = 860 kcal
- 04Daily cups = 860 / 400 = 2.1 cups
- 05Monthly cost = 2.1 x 0.25 lb x 30 x $3 = $47.25
Ready to run the numbers?
Open Pet Food Calculator