This dog food calculator tells you how much to feed each day, in cups (or cans) and calories, once you enter your dog’s weight, life stage and the calories in your food. For a rough sense of scale: a spayed or neutered adult pet dog needs about 35 calories per pound of body weight at 10 lb, but only about 20 calories per pound at 100 lb. Small dogs simply burn more energy per pound.
How to use the dog food calculator
- Weigh your dog. A bathroom scale works fine. Weigh yourself, then weigh yourself holding your dog, and subtract. If your dog needs to slim down, enter the target weight your vet recommends, not the current one.
- Pick the life stage and activity level. Most spayed or neutered family pets belong under “Adult, spayed/neutered”. Save the working-dog options for dogs that actually put in hours of work a day.
- Find the calories in your food. Look for “kcal/cup” or “kcal/can” on the bag or can. It’s usually near the guaranteed analysis. Not printed? Check the brand’s website.
- Choose meals per day. Adult dogs typically get two meals; puppies usually eat three or four.
How much should I feed my dog? Quick chart
Here are typical daily calories for healthy, spayed or neutered adult dogs with normal activity (RER × 1.6), plus the cups of an average 380 kcal/cup kibble. For your own dog and food, use the calculator above.
| Dog’s weight | Calories per day | Cups per day (380 kcal/cup) |
|---|---|---|
| 5 lb (2.3 kg) | 207 kcal | about 1/2 cup |
| 10 lb (4.5 kg) | 348 kcal | about 7/8 cup |
| 20 lb (9.1 kg) | 585 kcal | about 1 1/2 cups |
| 30 lb (13.6 kg) | 794 kcal | about 2 1/8 cups |
| 40 lb (18.1 kg) | 985 kcal | about 2 5/8 cups |
| 50 lb (22.7 kg) | 1,164 kcal | about 3 1/8 cups |
| 60 lb (27.2 kg) | 1,335 kcal | about 3 1/2 cups |
| 70 lb (31.8 kg) | 1,498 kcal | about 4 cups |
| 80 lb (36.3 kg) | 1,656 kcal | about 4 3/8 cups |
| 100 lb (45.4 kg) | 1,958 kcal | about 5 1/8 cups |
Look at how the calories climb. They don’t go up in a straight line. A 100 lb dog eats about five and a half times what a 10 lb dog does, not ten times. Smaller bodies lose heat faster, so they burn more per pound.
How the calculator works
It uses the same two-step method vets use for nutrition.
Step 1: Resting Energy Requirement (RER)
RER is what your dog would burn lying still in a comfortable room all day:
RER = 70 × (body weight in kg)0.75
Say your dog weighs 20 kg (44 lb). That’s 70 × 200.75 ≈ 662 kcal per day.
Step 2: Maintenance Energy Requirement (MER)
Real dogs don’t lie still. They walk, play, grow and keep warm, so RER gets multiplied by a life-stage factor:
| Life stage / activity | Factor (× RER) |
|---|---|
| Adult, spayed or neutered | 1.6 |
| Adult, intact | 1.8 |
| Senior or low activity | 1.4 |
| Inactive or prone to weight gain | 1.2 |
| Weight loss (at target weight) | 1.0 |
| Puppy under 4 months | 3.0 |
| Puppy 4–12 months | 2.0 |
| Active / light work | 2.0 |
| Moderate work | 3.0 |
| Heavy work | 4.0–8.0 (we use 5.0) |
Last, we divide the daily calories by the calories in one cup or can of your food. This is why the kcal number on the label matters so much. Two foods can differ by 100+ kcal per cup, and over a month that adds up fast.
Is my dog at the right weight?
The numbers get you started. Your dog’s body tells you if they’re right. Vets use a 9-point Body Condition Score (BCS), and a 4 or 5 is ideal. You’re in good shape if:
- you can feel the ribs easily under a thin layer of fat, without pressing hard
- there’s a clear waist behind the ribs when you look down from above
- the belly tucks up from the chest toward the hind legs when you look from the side.
Can’t find the ribs, or no waist? Cut the daily amount by about 10% and recheck in 2–4 weeks. If the ribs, spine or hip bones stand out, add 10% and talk to your vet.
Tips for feeding the right amount
- Use a real measuring cup. A pet store “scoop” or a coffee mug can hold 1.5–2 real cups. A kitchen scale beats both.
- Count the treats. Treats, chews and table scraps should stay under 10% of daily calories, and the calculator shows your dog’s treat budget.
- Recalculate whenever you change foods. A different kcal per cup means a different portion, even if the bag looks almost the same.
- Dogs that are much more active in summer, or spend winters outdoors, may need more food at those times of year.
- Switch foods slowly, over 7–10 days, to avoid an upset stomach.
Frequently asked questions
How many cups of food should my dog eat a day?
It depends on weight and how rich the food is. A 30 lb adult neutered dog eating a 380 kcal/cup kibble needs about 2 1/8 cups a day, split into two meals. A 60 lb dog needs about 3.5 cups. The calculator gives your dog’s exact amount.
Is the feeding guide on the dog food bag accurate?
It’s a fair starting range, but it often runs high. Bag guides are written for fairly active, intact dogs, not spayed or neutered pets that rest most of the day. Many owners find their dog needs 10–20% less than the bag says.
How much should I feed my puppy?
About three times their resting energy until 4 months, then about twice until they’re grown. Pick the puppy option in the calculator and recalculate every couple of weeks as your puppy gains weight. Large-breed puppies should grow steadily, not fast, so don’t overfeed.
How much should I feed my dog to lose weight?
Feed for the target weight, not the current one. Choose “Weight loss” and enter the goal weight. That gives roughly RER at the ideal weight, which usually means a safe loss of 1–2% of body weight per week. Weigh your dog every two weeks and plan the diet with your vet.
How many times a day should a dog eat?
Two meals a day suits most adult dogs, about 8–12 hours apart. Puppies need three or four. Large, deep-chested breeds may do better with smaller, more frequent meals.
Can I use the calculator for wet food?
Yes. Choose “Wet / canned food” and enter the kcal per can. Feeding a mix? Work out how many calories come from the wet part, subtract that from the daily total, and feed the rest as kibble.