How to Calculate the Right Food Portion for Your Dog

Feeding your dog the right amount of food is one of the most important things you can do for their health and happiness. Too much food can lead to obesity and related health problems. Too little can leave your pup undernourished and lacking energy. But how do you know exactly how much to feed? The answer isn't as simple as just following the feeding chart on the bag. Those charts are only a starting point. The right way to calculate your dog's food portion is based on their individual needs. Use science-backed formulas and the information on the food label.

In this guide, we'll walk you through the step-by-step process to calculate your dog's ideal daily food portion. We'll explain why this method is more accurate than generic feeding charts. We'll also share practical tips to keep your dog healthy and happy.

Why Generic Feeding Charts Aren’t Enough

Most dog food bags include a feeding chart that suggests how much to feed based on your dog’s weight. While these charts are helpful, they don’t account for important factors like:

Your dog’s age and life stage (puppy, adult, senior)
Whether your dog is neutered or intact
Their activity level
Their metabolism and body condition

For example, a highly active working dog needs far more calories than a couch-loving senior, even if they weigh the same. That’s why the most accurate way to determine your dog’s food portion is to calculate their energy needs and match it to the calorie content of their food.

Step-by-Step: How to Calculate Your Dog’s Food Portion

Step 1: Find the Calorie Content on the Label

Every dog food label is required by the Association of American Feed Control Officials (AAFCO) to list the calorie content. This is usually shown as:

kcal/kg (kilocalories per kilogram of food)
kcal/cup or kcal/treat (kilocalories per familiar household unit)

Look for the “Calorie Content” section on the label. (AAFCO requirement)

Step 2: Calculate Your Dog’s Resting Energy Requirement (RER)

The Resting Energy Requirement (RER) is the number of calories your dog needs just to maintain basic bodily functions at rest. The formula is:

RER = 70 × (body weight in kg)^0.75

For example, if your dog weighs 20 kg:

RER = 70 × (20)^0.75 = 70 × 8.71 = 609.7 kcal/day

Step 3: Apply the Life Stage and Activity Factor

Now, multiply the RER by a factor that reflects your dog’s life stage and activity level:

Life Stage / Condition	Factor
Neutered adult	1.6
Intact adult	1.8
Weight loss	1.0–1.2
Puppy (0–4 months)	3.0
Puppy (4–12 months)	2.0
High energy (working dogs)	2.0–5.0

For example, if your 20 kg neutered adult dog is at a healthy weight:

Daily energy requirement = RER × 1.6 = 609.7 × 1.6 = 975.5 kcal/day

Step 4: Calculate How Much Food to Feed

Now, divide your dog’s daily energy requirement by the calorie density of their food (from the label) to get the amount of food to feed per day.

For example, if your food has 3,500 kcal/kg:

Food needed (kg/day) = Daily energy requirement / kcal per kg
= 975.5 / 3,500 = 0.279 kg/day

Convert to pounds if needed (1 kg = 2.2 lbs):

0.279 kg × 2.2 = 0.61 lbs/day

Step 5: Adjust for Body Condition and Activity

This calculation gives you a starting point. Monitor your dog’s body condition and adjust as needed:

If your dog is gaining weight, reduce food by 10–15%.
If your dog is losing weight, increase food by 10–15%.
Re-calculate every few months, especially if your dog’s weight, activity level, or life stage changes.

Practical Tips for Feeding Your Dog

Use a kitchen scale to measure food for accuracy. Measuring cups can vary.
Weigh your dog regularly to track changes and adjust food portions.
Read the label carefully—calorie content can vary widely between brands and formulas.
Consult your vet if you’re unsure about your dog’s energy needs or if they have health issues.

Why This Method Is Better Than Feeding Charts

Feeding charts on dog food bags are based on averages and don’t account for individual differences. By calculating your dog’s energy needs and matching it to the calorie content of their food, you ensure they get the right amount for their unique needs.

Pro Tip: Apps like Doggo Eats make this process easy without needing to do all these manual calculations.

Common Mistakes to Avoid

Overfeeding treats and table scraps—these can add up quickly and throw off your calculations.
Ignoring changes in activity or weight—your dog’s needs change over time.
Relying solely on feeding charts—they’re a starting point, not a rule.

When to Re-Calculate

Re-calculate your dog’s food portion whenever:

Their weight changes by more than 10%
Their activity level changes (e.g., more exercise, less exercise)
They enter a new life stage (puppy to adult, adult to senior)
You switch to a new food with a different calorie content

Final Thoughts

Feeding your dog the right amount of food is essential for their health and well-being. By using the RER formula and the calorie content on the label, you can calculate a portion that’s tailored to your dog’s individual needs. This method is more accurate than generic feeding charts and helps prevent overfeeding or underfeeding.

Remember, your dog’s needs can change over time, so it’s important to re-calculate their portion regularly. With a little math and attention to detail, you can keep your dog healthy, happy, and at their ideal weight.

By following these steps, you’ll be feeding your dog the right amount every time. And with tools like Doggo Eats, it’s easier than ever to keep your dog’s diet on track with right food and portions.