Dog Calorie Calculator
How many calories does my dog need? Enter a body weight and this dog calorie needs calculator gives the resting energy requirement (RER) and daily maintenance energy requirement (MER) used in veterinary nutrition. Free, unlimited, no account required.
Calculate daily calories
Resting energy (RER)
662 kcal / day
Daily energy (MER)
1059 kcal / day
This is an estimate for healthy adult dogs. Growing puppies, pregnant or lactating dogs, and patients on therapeutic diets need a veterinary feeding plan.
Turn calories into a portion
Calories are only the middle step — what you actually feed is grams. Take the energy figures from the bag or tin label and get the daily portion.
Usually printed as “metabolisable energy” on the label.
Only some labels give this. Grams are always more accurate than cups.
Daily portion
286 g / day
Your label says 3700 kcal per kg, so feed about 286 g per day to reach 1059 kcal.
In cups
Add the kcal per cup from the label to see a cup measure. Cups vary a lot between foods, so weigh the food when you can.
Free beta tool: full dashboard coming
This public calculator is free while Vet.Portions is in beta. A free user account unlocks the full product catalogue, printable client handouts, puppy growth plans, prescription diet support, food transitions, and parasite dosing for your clinic.
How the dog calorie calculation works
Every veterinary calorie calculator starts with the resting energy requirement, the energy a dog uses at rest before exercise, growth, reproduction or temperature stress. It is calculated with the allometric equation:
A 20 kg dog therefore has a RER of about 662 kcal per day. RER alone is not a feeding recommendation; it is multiplied by a life-stage factor to give the maintenance energy requirement:
Life-stage factors for dogs
| Patient | Factor |
|---|---|
| Neutered adult dog | RER × 1.6 |
| Intact adult dog | RER × 1.8 |
| Weight loss dog | RER × 1.0 |
| Weight gain dog | RER × 1.7 |
| Active / working dog | RER × 2.5 |
| Senior, low activity dog | RER × 1.4 |
RER chart for dogs by body weight
Resting energy requirement at a glance, with the two most common adult maintenance factors. Use it as a sanity check on the calculator above.
| Weight | RER (kcal/day) | Neutered adult (×1.6) | Intact adult (×1.8) |
|---|---|---|---|
| 2 kg (4.4 lb) | 118 | 189 | 212 |
| 5 kg (11 lb) | 234 | 374 | 421 |
| 10 kg (22 lb) | 394 | 630 | 709 |
| 15 kg (33.1 lb) | 534 | 854 | 961 |
| 20 kg (44.1 lb) | 662 | 1059 | 1192 |
| 25 kg (55.1 lb) | 783 | 1253 | 1409 |
| 30 kg (66.1 lb) | 897 | 1435 | 1615 |
| 40 kg (88.2 lb) | 1113 | 1781 | 2003 |
| 50 kg (110.2 lb) | 1316 | 2106 | 2369 |
| 60 kg (132.3 lb) | 1509 | 2414 | 2716 |
Chart values are rounded. Growing, pregnant, lactating, underweight or hospitalised patients use different factors and need a veterinary feeding plan.
From calories to grams of food
Once you have the daily calorie target, divide it by the food’s energy density to get the daily ration:
Most dry dog foods sit between 3.2 and 4.2 kcal per gram, so the same calorie target can mean very different bowl sizes. Vet.Portions holds the calorie content of thousands of regional products so your team never has to look it up on the bag.
Built for veterinary clinics
The full Vet.Portions dashboard turns this calculation into a printable client handout, with product-specific gram amounts, meal splits, growth plans for puppies and kittens, and parasite dosing support.
Frequently asked questions
- How many calories does my dog need per day?
- Calculate RER = 70 × (weight in kg)0.75, then multiply by the factor that matches the dog. A 20 kg neutered adult dog needs roughly 1,060 kcal per day.
- What is the difference between RER and MER?
- RER is resting energy at complete rest. MER adds activity, thermoregulation and tissue maintenance to give a realistic daily target.
- Is a veterinary calorie calculator accurate for every dog?
- No. It is a clinical support tool. Recheck body weight and body condition every two to four weeks and adjust the amount with your veterinarian.