October 16, 2026
How much to feed a dog: a simple guide by weight
Quick answer: Start with the feeding guide on your dog’s food for their ideal weight, not their current weight. Weigh every meal, count treats, then check your dog’s body condition every two to four weeks and adjust the amount by about 10% at a time. The right amount is the one that keeps your dog lean, with ribs you can feel easily and a visible waist.
“How much should I feed my dog?” sounds like it should have one simple answer. It doesn’t, because two dogs of the same weight can need very different amounts. Age, neutering, activity, breed and the food itself all play a part. Here’s how to find the right amount for your dog.
Start with the feeding guide on the bag
Every complete dog food has a feeding table, and it’s the best starting point because it’s based on that food’s calorie content. Two things to keep in mind:
- Use your dog’s ideal weight. If your dog is overweight, feeding for their current weight keeps them overweight.
- Treat it as a range, not a rule. Feeding guides are written for an average dog. Many pet dogs, especially neutered and less active ones, need less than the bag suggests.
How many calories does a dog need?
Vets estimate a dog’s needs in two steps, using the 2021 AAHA Nutrition and Weight Management Guidelines:
- Resting energy requirement (RER) = 70 Ă— (body weight in kg)0.75
- Daily need = RER Ă— a life-stage factor, for example 1.4 to 1.6 for a neutered adult, 1.6 to 1.8 for an intact adult, 1.0 to 1.2 for an inactive or weight-gain-prone dog, 3.0 for a puppy under four months and 2.0 for an older puppy.
Here’s what that works out to for healthy adult dogs at their ideal weight. These are starting estimates only:
| Ideal weight | Neutered adult (kcal/day) | Inactive or prone to weight gain (kcal/day) |
|---|---|---|
| 5 kg | 330 to 370 | about 230 to 280 |
| 10 kg | 550 to 630 | about 390 to 470 |
| 20 kg | 930 to 1,060 | about 660 to 790 |
| 30 kg | 1,260 to 1,440 | about 900 to 1,080 |
| 40 kg | 1,560 to 1,780 | about 1,110 to 1,340 |
AAHA notes that indoor or less active dogs may need even less than these ranges. Working dogs, pregnant or nursing dogs and puppies need more, and your vet should guide those.
Turning calories into grams
Find the calorie content on the bag or the product page, usually given as kcal per kg or per 100 g. Divide your dog’s daily calories by the calories per gram.
Example: a 20 kg neutered dog needs roughly 930 to 1,060 kcal a day. A dry food with 3,700 kcal/kg has 3.7 kcal per gram, so that’s about 250 to 285 g of food a day, split into meals. If you feed wet food or toppers too, count those calories and reduce the dry food to match.
Check body condition, then adjust
The formula and the bag both get you close. Your dog’s body tells you the rest. Vets use the WSAVA body condition score, a 1 to 9 scale where 4 to 5 is ideal:
- Ideal (4 to 5): you can feel the ribs easily under a thin layer of fat, see a waist from above, and see the tummy tuck up from the side.
- Overweight (6 to 7): the ribs are harder to feel, the waist is faint or missing, and fat builds up over the lower back and base of the tail.
- Obese (8 to 9): you can’t feel the ribs without pressing hard, and there’s no waist or tummy tuck.
Check every two to four weeks and weigh your dog if you can. If your dog is gaining, reduce the daily amount by about 10%. If your dog is too thin, increase it by about 10%. Then check again. If your dog keeps losing or gaining weight without a change in food, see your vet.
How many meals a day?
- Puppies: several small meals a day. Our puppy food guide covers this in more detail.
- Adults: most dogs do well on two measured meals a day.
- Large, deep-chested breeds: two or more smaller meals are usually preferred to one big meal.
Leaving food out all day makes it hard to know how much your dog eats, and it’s an easy route to weight gain.
Common feeding mistakes
- Using a scoop or cup. Volume measures can be off by a lot. A kitchen scale is the most accurate tool.
- Forgetting treats. Treats, chews and table food should be no more than about 10% of daily calories. Take them off the main meal.
- Not adjusting after neutering. Neutered dogs often need fewer calories, so watch their weight closely in the months after the operation.
- Switching foods but keeping the same scoop. Calorie content varies a lot between foods, so recalculate whenever you change food, and switch gradually over about a week.
- Feeding by the empty bowl. Most dogs will eat whatever you put down. Go by body condition, not appetite.
Small and large dogs
Small dogs need more calories per kilogram than big dogs, which is why the table above doesn’t scale in a straight line. Small-breed foods are often more energy-dense with a smaller kibble, so portions look tiny. Browse small breed dog food for options.
Large dogs are more prone to joint strain from extra weight, so keeping them lean matters even more. See our large breed dog food page. If your dog already needs to lose weight, our weight control dog food range is designed to keep them full on fewer calories. Ask your vet for a target weight first.
Your feeding checklist
- You know your dog’s ideal weight.
- You’ve checked the calorie content of the food you feed.
- You weigh meals on a kitchen scale.
- Treats stay under about 10% of daily calories.
- You check body condition every two to four weeks and adjust by about 10%.
- You recalculate whenever you change food, life stage or activity level.
Where to start
Browse all dog food, or go straight to puppy food or senior dog food. Our product pages include feeding guides where the manufacturer provides them.
Once you know how much your dog eats, Autoship can deliver the right bag before you run out, with 35% off your first order (up to R400) and 5% off after that. Not sure how much to feed? Chat to us on WhatsApp or email hello@zuki.co.za.
This guide is general information for healthy dogs. If your dog has a health condition, is pregnant or nursing, or is losing or gaining weight unexpectedly, ask your vet for a tailored plan.
Frequently asked questions
Start with the feeding guide on the food for your dog’s ideal weight, then adjust. As a rough guide, a neutered 20 kg adult needs about 930 to 1,060 kcal a day, or roughly 250 to 285 g of a dry food with 3,700 kcal/kg. Check body condition every two to four weeks and adjust by about 10%.
Your dog should have ribs you can feel easily under a thin layer of fat, a visible waist from above and a tummy that tucks up from the side. That’s a body condition score of 4 to 5 out of 9. If your dog is gaining weight, cut back by about 10%.
Most adult dogs do well on two measured meals a day. Puppies need several smaller meals, and large, deep-chested dogs are usually better on two or more smaller meals than one big one.
Yes. Treats, chews and table food should make up no more than about 10% of your dog’s daily calories, and you should reduce their main meals to match.