How Much Should I Feed My Dog a Day? Dog Food Calculator
Most dog bowls are filled by guesswork, and that guesswork is why so many pet dogs carry extra weight. The scoop that came with the bag is not a measuring cup, and the chart on the back is written for “average” dogs that may not look like yours.
Quick answer: an adult, spayed or neutered dog needs about 1.6 times its resting energy, where resting energy = 70 × (weight in kg)^0.75 kilocalories. For a 10 kg adult dog that is about 630 kcal a day, or roughly 180 g of a 350 kcal per 100 g dry food. The calculator below works it out for your dog’s weight, life stage and food.
Daily Dog Food Amount Calculator
Enter your dog’s current weight (or ideal weight if your vet says they are overweight), choose a life stage and type the calories per 100 g from your food label. The tool shows daily calories and grams, plus a per-meal amount for two meals.
Daily Dog Food Amount Calculator
Important: this is a general guide, not a prescription. Ask your vet before changing your dog’s diet, especially for puppies, pregnant dogs, seniors or dogs with health problems.
How the Calculator Works
Vets and pet nutritionists usually start with two numbers.
1. Resting Energy Requirement (RER)
RER is the energy a dog burns at rest just to keep the body running. The common formula is:
RER = 70 × (body weight in kg)^0.75
The power of 0.75 matters. Small dogs burn more energy per kilo than big dogs, so a 30 kg dog does not need three times the food of a 10 kg dog. It needs about 2.3 times.
2. Daily Energy Requirement (MER)
Next, RER is multiplied by a life-stage factor. These are the factors the calculator uses, based on widely used veterinary guidelines:
| Life stage | Factor × RER |
|---|---|
| Puppy under 4 months | 3.0 |
| Puppy 4 to 12 months | 2.0 |
| Adult, spayed or neutered | 1.6 |
| Adult, intact | 1.8 |
| Active or working adult | 2.0 |
| Senior or less active | 1.4 |
| Weight loss (use ideal weight) | 1.0 |
3. Converting Calories to Grams
Every food has a different energy density. Dry kibble often has 330 to 420 kcal per 100 g, while wet food is usually 70 to 120 kcal per 100 g because it is mostly water. The calculator divides daily calories by your food’s kcal per 100 g and multiplies by 100 to give grams.
Dog Food Amount Chart by Weight
The table below assumes an adult, neutered dog (factor 1.6) eating dry food with 350 kcal per 100 g. Use it as a starting point only.
| Dog weight | Calories per day | Dry food per day |
|---|---|---|
| 5 kg | about 375 kcal | about 107 g |
| 10 kg | about 630 kcal | about 180 g |
| 15 kg | about 855 kcal | about 244 g |
| 20 kg | about 1,060 kcal | about 303 g |
| 30 kg | about 1,436 kcal | about 410 g |
| 40 kg | about 1,782 kcal | about 509 g |
Worked Examples
Example 1: A 20 kg neutered adult Indie dog
RER = 70 × 20^0.75 = about 662 kcal. Daily need = 662 × 1.6 = about 1,059 kcal. With a food of 360 kcal per 100 g, that is 1,059 ÷ 360 × 100 = about 294 g a day, or about 147 g per meal if you feed twice a day.
Example 2: A 5 kg puppy, six months old
RER = 70 × 5^0.75 = about 234 kcal. Daily need = 234 × 2.0 = about 468 kcal. With puppy food at 400 kcal per 100 g, that is about 117 g a day, best split into three meals at this age. Growing puppies need puppy food, not adult food. Our puppy vaccination schedule guide is a good companion for the first-year plan.
Example 3: A 30 kg dog that needs to lose weight
Your vet says the ideal weight is 26 kg. Use 26 kg and the weight-loss factor 1.0: RER = 70 × 26^0.75 = about 807 kcal a day. Weigh food on a kitchen scale and recheck weight every two to four weeks.
How to Check If the Amount Is Right
Calculators give a starting point. Your dog’s body gives the final answer. Use a simple body condition check every two weeks:
- Ribs: you should feel them easily with light pressure, like the back of your hand.
- Waist: looking from above, you should see a waist behind the ribs.
- Belly: from the side, the belly should tuck up toward the back legs.
If your dog is gaining weight, reduce food by about 10%. If they look thin, add about 10%. The calculator shows this 10% range for you. Change slowly and recheck after two weeks.
Smart Feeding Tips
- Weigh, do not scoop. A kitchen scale is the cheapest health tool you can buy. A heaped scoop can be 20% more than a level one.
- Count treats. Treats, chews and table scraps should be no more than 10% of daily calories. Subtract them from the bowl.
- Split meals. Two meals a day suit most adults; puppies do better on three or four.
- Read the label. Look for “kcal/kg” or “kcal per cup” on the bag. Divide kcal/kg by 10 to get kcal per 100 g.
- Mixing wet and dry? Work out the calories from each and keep the total equal to the calculator’s daily number.
- Fresh water always. Dogs on dry food drink more, so keep a clean bowl full.
For choosing the food itself, see our guide to the best dog food choices, and for age-based changes read feeding your dog at every stage.
Why Feeding the Right Amount Matters
Overweight dogs face more arthritis, diabetes, breathing problems and a shorter life. A well-known long-term study of Labrador Retrievers found that dogs kept lean lived around two years longer than their littermates that were fed more. Underfeeding is a problem too, especially for puppies whose bones and muscles are still developing. The goal is a steady, healthy body shape, not an empty or overflowing bowl.
Feeding Different Types of Dogs
Puppies
Puppies need more energy per kilo than adults because they are building bones, muscles and organs. Feed a complete puppy food, use the puppy factors in the calculator and weigh your puppy every week. Large-breed puppies should grow steadily, not fast, because rapid growth can strain developing joints. Switch to adult food at around 12 months for small and medium breeds and 15 to 18 months for large and giant breeds, as your vet advises.
Seniors
Older dogs usually move less and burn fewer calories, so the senior factor of 1.4 is a sensible start. Some seniors, though, lose weight because of dental pain or illness, so a sudden change in appetite always deserves a vet visit.
Working and Very Active Dogs
Dogs that run, herd or train for hours a day can need double their resting energy or more. Increase food gradually and watch body shape rather than the bowl.
Common Feeding Mistakes to Avoid
- Free-feeding (leaving the bowl full all day), which makes it impossible to know how much your dog eats.
- Using a coffee mug or random scoop instead of a scale.
- Forgetting chews, biscuits and table scraps in the daily total.
- Changing food suddenly. Mix the new food in over 7 to 10 days to avoid stomach upsets.
- Feeding human foods that are toxic to dogs, such as onion, garlic, grapes, raisins, chocolate and xylitol sweetener.
FAQ
How much should I feed my dog a day?
Start with the calorie formula: 70 × weight^0.75, multiplied by a life-stage factor such as 1.6 for neutered adults. Then convert calories to grams using your food label. The calculator above does all three steps.
Should I feed my dog once or twice a day?
Most adult dogs do well on two meals a day, about 8 to 12 hours apart. Puppies need three to four small meals. Some large deep-chested breeds benefit from smaller meals to lower the risk of bloat.
Are the feeding charts on dog food bags accurate?
They are a reasonable start but often generous, because they are designed for active dogs. Many pet dogs need 10% to 20% less. Watch your dog’s body shape and adjust.
How much wet food should I give my dog?
Wet food has far fewer calories per gram. Enter its kcal per 100 g (often 80 to 110) in the calculator. Your dog will need roughly three to four times more grams of wet food than dry food.
Is this dog food calculator a replacement for my vet?
No. It is a general guide based on standard formulas. Dogs with medical conditions, pregnant or nursing dogs and very old dogs can need very different amounts, so always ask your vet.
General guide only. Please ask your vet about the right diet and amount for your own dog.
