How to use the dog calorie calculator
- Enter weight.
- Pick the life stage or activity.
- Press Calculate.
Worked example
A neutered adult dog weighing 30 kg.
- Weight
- 30 kg
- Life stage
- Neutered/spayed adult
- RER (70 × kg^0.75)
- 897 kcal/day
- MER for this life stage
- 1,436 kcal/day
Example values are illustrative; this result is produced by the same calculator above.
How we calculate it
Sources: NRC · Merck Veterinary Manual
Reference table
| Weight | RER kcal/day | Neutered adult (1.6×) |
|---|---|---|
| 2 kg | 118 | 188 |
| 5 kg | 234 | 374 |
| 10 kg | 394 | 630 |
| 15 kg | 534 | 854 |
| 20 kg | 662 | 1,059 |
| 25 kg | 783 | 1,252 |
| 30 kg | 897 | 1,436 |
| 40 kg | 1,113 | 1,781 |
| 50 kg | 1,316 | 2,106 |
Understanding your result
RER, the resting energy requirement, is the energy a dog needs at rest: 70 × body weight in kg to the power 0.75. For a 30 kg dog it is about 897 kcal a day. MER, the maintenance energy requirement, multiplies RER by a factor for life stage and activity.
The factors used here are 1.6 for a neutered adult, 1.8 for an intact adult, 1.4 for an inactive dog that gains weight easily, 2.0 for light work, 3.0 for moderate work, 1.0 (of ideal weight) for weight loss, 3.0 for puppies under four months and 2.0 for puppies from four months to adulthood.
Use the energy figure with the kcal on your dog food's label to work out portions, or use it to check whether your current feeding matches the estimate.
Common mistakes
- Mixing up RER and MER; RER alone is not a daily feeding target for most dogs.
- Choosing a work factor for an ordinary pet dog. Most family dogs are neutered adults.
- Using the weight-loss option with the current weight; it expects the ideal weight.
- Forgetting that treats and table scraps add calories.
Good to know
- Energy needs differ between individual dogs of the same weight, and between breeds.
- Always adjust according to body condition and weight change over several weeks.
- For a weight-loss diet, a vet check first is recommended.
When to talk to your vet
- Weight loss or gain you can't explain
- Before a weight-loss diet
Frequently asked questions
How many calories does a dog need?
Start with RER = 70 × weight(kg)^0.75. A 30 kg dog's RER is about 897 kcal; a neutered adult needs about 1.6 × that.
What is RER?
Resting Energy Requirement: the calories needed at rest in a comfortable environment.
What is MER?
Maintenance Energy Requirement: RER multiplied by a factor for life stage and activity, from 1.0 (weight loss) to 3.0 or more (puppies, working dogs).
How many calories should my dog eat to lose weight?
Vets often start at 1.0 × RER of the dog's ideal weight and adjust every few weeks.
Why are my dog's calories different from the food bag?
Bag charts are broad ranges. This calculator starts from resting energy and applies a life-stage factor, so it is tailored to weight and status. Weigh your dog every few weeks and adjust in small steps based on body condition.
Which life-stage factor should I choose?
Neutered adult 1.6, intact adult 1.8, inactive or weight-gain-prone dogs 1.2–1.4 (we show 1.4), light work 2.0 and moderate work 3.0. If you are unsure, pick the closest one and monitor body condition.
Sources
- NRC (2006) Nutrient Requirements of Dogs and Cats, National Academies Press
- Merck Veterinary Manual — Nutritional Requirements of Small Animals (incl. maintenance energy table)
Related calculators
- Dog Food CalculatorFind out how many calories your dog needs each day and how many grams or cups of your dog's food that is — using the same energy formula vets use.
- Puppy Food CalculatorCalculate how much a growing puppy needs, how many meals a day, and how much per meal.
- Raw Dog Food CalculatorEstimate how much raw food to feed each day and how to split it into muscle meat, bone and organ.
- Dog Food CalorieEstimate the calories in a dog or cat food from the guaranteed analysis on the label.
Estimates only. Every pet is different — confirm with your veterinarian. If your pet may have eaten something harmful, contact your vet or an animal poison helpline now.