Dog Calorie Calculator

Estimate your dog's daily calorie needs (kcal/day) from body weight and life stage using RER = 70 × kg0.75 and standard maintenance factors.

Quick Facts

Method
RER = 70 × (kg)0.75, then MER = RER × life-stage factor
Allometric resting-energy equation used in veterinary nutrition; 1 kg = 2.2046 lb.

Your Results

Calculated
Daily calories (MER)
-
What to feed per day
Resting energy (RER)
-
Calories burned at rest
Life-stage factor
-
Multiplier applied to RER
Body weight
-
Used in the formula

Ready

Enter your dog's weight and life stage, then calculate.

How the Dog Calorie Calculator works

This tool estimates how many calories (kilocalories, kcal) your dog needs each day. It uses the two-step method taught in veterinary nutrition: first the Resting Energy Requirement (RER), then the Maintenance Energy Requirement (MER).

The formula

The RER is an allometric equation, meaning energy scales with body mass raised to a power rather than linearly:

RER = 70 × (body weight in kg)0.75 kcal/day

Because metabolism does not scale one-to-one with weight, a dog twice as heavy does not need twice the calories. The 0.75 exponent captures the fact that larger animals burn fewer calories per kilogram than smaller ones. Body weight in pounds is converted first: 1 lb = 0.4536 kg.

The MER is the RER multiplied by a factor for the dog's life stage and activity level:

MER = RER × life-stage factor

Standard life-stage factors

These multipliers are the widely published maintenance factors used by veterinary nutritionists (based on National Research Council and WSAVA guidance):

  • Weight loss (obese-prone): 1.0 × RER
  • Senior or inactive: 1.4 × RER
  • Neutered adult (typical pet): 1.6 × RER
  • Intact adult: 1.8 × RER
  • Active / light work: 2.0 × RER
  • Puppy (0-4 months) or heavy work: 3.0 × RER (puppies over 4 months to adult size use about 2.0 × RER)

Worked example

For a 10 kg neutered adult dog: RER = 70 × 100.75 = 70 × 5.623 = about 394 kcal/day. MER = 394 × 1.6 = about 630 kcal/day. That is the daily amount to feed as a starting point.

Common reference points

  • 5 kg (11 lb) neutered adult: RER about 234, MER about 375 kcal/day.
  • 10 kg (22 lb) neutered adult: RER about 394, MER about 630 kcal/day.
  • 20 kg (44 lb) neutered adult: RER about 662, MER about 1,059 kcal/day.
  • 30 kg (66 lb) neutered adult: RER about 897, MER about 1,436 kcal/day.

Turning calories into food

To convert the calorie target into a portion, divide by the calorie density of the food. Dry kibble is often around 350-450 kcal per cup, and the value is printed on the bag as the metabolizable energy (ME). For example, 630 kcal/day divided by 400 kcal/cup is about 1.6 cups per day.

Frequently Asked Questions

How many calories does my dog need per day?
Compute RER = 70 × (weight in kg)0.75, then multiply by the life-stage factor. A typical neutered adult uses 1.6 × RER. Example: a 10 kg neutered adult needs about 630 kcal/day (RER 394 × 1.6).
What is the difference between RER and MER?
RER (Resting Energy Requirement) is what a dog burns at rest: 70 × kg0.75 kcal/day. MER (Maintenance Energy Requirement) is RER scaled up by an activity/life-stage factor to cover normal daily movement, growth, or reproduction. MER is the number you feed to.
Why is the formula not just calories-per-pound?
Energy needs scale with metabolic body size, roughly weight0.75, not linear weight. A 30 kg dog needs about 2.3 times the resting calories of a 10 kg dog, not 3 times. The 0.75 exponent is why small breeds need proportionally more calories per kilogram than large breeds.
How accurate is this estimate?
The RER equation is well validated, but the MER factors are population averages. An individual dog can differ 20 percent or more based on breed, metabolism, coat, spay/neuter status, and climate. Treat the result as a starting point, weigh your dog every 2 to 4 weeks, and adjust the amount to maintain a lean body condition (ribs easily felt, visible waist).

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