Food is usually the largest regular cost of a dog, and it is also the one you control best. Yet many owners only know what a bag costs, not what a day or a month costs, and they cannot tell whether a pricier food is really dearer or a cheaper one a bargain. The answer comes from three numbers: how many calories your dog needs, how many calories are in a kilogram of the food and what a kilogram costs. This guide walks through the sum, gives a table for dogs from 5 to 40 kg at four example prices, explains why energy density matters and shows how to compare foods and trim the bill without cutting care. All prices are illustrations in one currency; use your own in the Dog Food Cost Calculator.
The three steps
- Daily calories. For a neutered adult, 1.6 × 70 × weight in kg ^ 0.75. The Dog Food Calculator does this, and our guide to how much to feed a dog explains the factors.
- Daily grams. Divide calories by the food’s kcal per gram (kcal per kg ÷ 1,000).
- Cost. Daily grams × 30 ÷ 1,000 × price per kg gives the monthly cost; multiply by 12 for the year.
A worked example for a 20 kg neutered dog on a 3,600 kcal/kg food at 4.00 per kg: 662 × 1.6 = 1,059 kcal; 1,059 ÷ 3.6 = 294 g; 294 × 30 ÷ 1,000 = 8.8 kg; 8.8 × 4.00 = 35.31 a month, or 424 a year.
A table by dog size and price
The table assumes neutered adults and a 3,600 kcal/kg food. The monthly cost is shown at four prices per kilogram.
| Dog | Daily kcal | Daily grams | Kg a month | At 3 per kg | At 4 per kg | At 5 per kg | At 6 per kg |
|---|---|---|---|---|---|---|---|
| 5 kg | 374 | 104 | 3.1 | 9.36 | 12.48 | 15.60 | 18.72 |
| 10 kg | 630 | 175 | 5.2 | 15.75 | 20.99 | 26.24 | 31.49 |
| 20 kg | 1,059 | 294 | 8.8 | 26.48 | 35.31 | 44.13 | 52.96 |
| 30 kg | 1,436 | 399 | 12.0 | 35.89 | 47.86 | 59.82 | 71.78 |
| 40 kg | 1,781 | 495 | 14.8 | 44.54 | 59.38 | 74.23 | 89.07 |
Two things stand out. Cost scales less than linearly with weight, because calories rise with weight to the power 0.75: a dog eight times heavier (5 kg to 40 kg) eats 4.8 times as much. And the price per kilogram matters as much as size: a 20 kg dog on the dearest food costs twice as much as one on the cheapest.
Why energy density matters
Foods differ in calories per kilogram. A cheaper bag that is less energy-dense may need more grams a day and cost the same, or more, per day than a pricier concentrated one.
| Food | Price per kg | kcal per kg | Grams for 1,059 kcal | Cost per day | Cost per 1,000 kcal |
|---|---|---|---|---|---|
| Food A | 3.20 | 3,300 | 321 | 1.03 | 0.97 |
| Food B | 4.00 | 3,600 | 294 | 1.18 | 1.11 |
| Food C | 5.50 | 4,200 | 252 | 1.39 | 1.31 |
| Food D | 4.50 | 3,300 | 321 | 1.44 | 1.36 |
Food D costs more per day than Food C even though its price per kg is lower, because it supplies fewer calories per kg. The comparison that does not mislead is cost per 1,000 kcal, which the Pet Food Price per 1,000 kcal Calculator computes. Cost is only one part of the choice: the food must be complete and balanced for your dog and suit any health needs, and your vet should guide that.
Treats, chews and extras
Treats can take up to 10% of daily calories and cost extra. If treats supply 106 kcal of the 1,059, the meals shrink to 953 kcal (265 g), saving about 10% of the meal cost, but the treats have a cost of their own. Specialty chews can cost far more per 1,000 kcal than kibble. Add them as a line: if you spend 12 a month on treats, the food total is the meals plus 12. See low-calorie dog treats for counting.
Wet food and mixed feeding
Wet food has a lower energy density, so the grams are several times larger, and the cost per 1,000 kcal is usually higher. A dog taking 25% of its calories from a wet food costing four times as much per 1,000 kcal raises the food bill by 75%, as the arithmetic in wet and dry dog food together shows. If you mix, work out each food’s share of calories and cost separately and add them.
Puppies and seniors
Puppies need more energy per kilogram, so a 10 kg puppy over 17 weeks (2.0 × RER) needs 787 kcal against 630 for a neutered adult, and 1,181 kcal if under 17 weeks. The bill rises quickly with growth, then settles; see the puppy feeding chart. Seniors may need more or less, depending on weight and health; ask your vet. A prescription diet usually costs more than a standard one, and your vet will explain why it is needed.
Buying smart
| Tactic | Notes |
|---|---|
| Compare cost per 1,000 kcal | The fairest comparison |
| Buy the bag size you can finish while fresh | A bigger bag saves only if used in time; see how long a bag lasts |
| Watch for price changes | Prices drift; recheck every few months |
| Subscribe only if the price per kg is lower | Check delivery fees and terms |
| Avoid wasting food | Weigh meals; seal and store properly |
| Do not overfeed | Extra food is extra cost and extra weight |
Quality matters more than the bottom price. A food that is complete and balanced, suits your dog and keeps it at a healthy weight is the best value, even if it is not the cheapest.
Building the number into a budget
Add the monthly food figure to the other regular lines in the Monthly Pet Budget Calculator, and to the lifetime view in the Cost of Owning a Dog Calculator. For a 20 kg dog at 35.31 a month, food costs 424 a year and about 5,090 over 12 years, before price changes. Our guide to the monthly cost of a dog lists the other lines.
| Years | Total at 25 a month | Total at 35 a month | Total at 50 a month |
|---|---|---|---|
| 5 | 1,500 | 2,100 | 3,000 |
| 10 | 3,000 | 4,200 | 6,000 |
| 12 | 3,600 | 5,040 | 7,200 |
| 15 | 4,500 | 6,300 | 9,000 |
Common mistakes
- Comparing price per bag or per kg only.
- Using the bag’s feeding guide instead of a calorie calculation.
- Forgetting treats and chews.
- Not recalculating when weight changes.
- Buying a huge bag that goes stale.
- Ignoring the cost of special diets.
- Cutting food below the dog’s needs to save money.
A worked year for one dog
Follow a single dog through a year to see how the monthly figure behaves. Max is a neutered 20 kg adult on a 3,600 kcal/kg food at 4.00 per kg, fed 294 g a day with 106 kcal of treats counted inside the allowance.
| Month | Weight | Daily grams | Food cost | Treat spend | Total |
|---|---|---|---|---|---|
| January | 20.0 kg | 294 g | 35.31 | 6.00 | 41.31 |
| April | 20.3 kg | 294 g | 35.31 | 6.00 | 41.31 |
| July | 20.1 kg | 294 g | 35.31 | 9.00 (training course) | 44.31 |
| October | 20.0 kg | 294 g | 35.31 | 6.00 | 41.31 |
Over twelve months, with an extra 3.00 in the summer course month, the total is about 499. The point of the table is that a dog at a steady weight on a measured amount has a steady bill. The surprises come from unmeasured scoops, uncounted treats and drifting weight. If Max had gained 2 kg through the year and the owner had increased food to match, the bill would have risen by about 7% for a worse outcome.
When prices change
Food prices move. A rise of 10% on a 35.31 monthly bill is 3.53 a month or 42 a year; a rise of 25% is 106 a year. Check your bill every few months, and look at the price per kilogram, the size of the bag and whether the maker has changed the formula, which can change the energy per kilogram and so the grams you need. When a price rises, recompute cost per 1,000 kcal for the food and one or two alternatives, so you decide on the numbers. If you switch, follow the steps in how to switch dog food, and recalculate the grams for the new energy value.
Estimating before you get a dog
If you are not yet a dog owner, you can estimate food costs from the adult weight your vet or breeder expects. Use the table with a mid-range price. A small dog of 5 to 10 kg costs roughly 12 to 26 a month at 4 to 5 per kg; a medium dog of 20 kg, 35 to 44; a large dog of 30 to 40 kg, 48 to 74. Puppies cost more per kilogram of body weight and the bill rises as they grow. Add the other regular costs from the Monthly Pet Budget Calculator, and compare dog and cat costs in our guide to dog vs cat cost.
Reading the sums for your own dog
Fill in this worksheet to compute your own bill.
| Step | Your number |
|---|---|
| Dog’s weight (kg) | |
| Daily calories (factor × 70 × kg ^ 0.75) | |
| Food kcal per kg | |
| Daily grams | |
| Price per kg | |
| Cost a month | |
| Treats and chews a month | |
| Total a month |
Quick summary
- Monthly cost = grams a day × 30 ÷ 1,000 × price per kg.
- A neutered 20 kg dog on 3,600 kcal/kg eats 294 g a day, 8.8 kg a month.
- Cost per 1,000 kcal is the fair comparison across foods.
- Add treats and extras as their own line.
- Recalculate when weight, food or price changes.
- Use the Dog Food Cost Calculator with your own price.
Frequently asked questions
How do I calculate dog food cost per month?
Daily grams × 30 ÷ 1,000 × price per kilogram. Get the daily grams from the dog's calories and the food's energy.
How much food does a 20 kg dog eat a month?
About 8.8 kg for a neutered adult on a 3,600 kcal/kg food (294 g a day).
Why does a bigger bag not always save money?
It does only if the price per kg is lower and the food stays fresh until used. Compare cost per 1,000 kcal.
How does energy density change cost?
A richer food needs fewer grams for the same calories, so a higher price per kg can still cost the same per day.
Should I include treats?
Yes. Treats can be up to 10% of calories and have their own cost.
How often should I recalculate?
When weight, activity, food or price changes, and at each life stage.
Does wet food cost more?
Usually per 1,000 kcal, yes. Compare using calories, not weight.
Sources
- NRC (2006) Nutrient Requirements of Dogs and Cats, National Academies Press
- Pure arithmetic on your own prices: month = grams a day × 30 ÷ 1,000 × price per kg
Related calculators
- Dog Food Cost CalculatorSee what it costs per day, month and year to feed your dog, from its calorie need and the price of the bag.
- Dog Food CalculatorTurn your dog's daily calorie need into grams and cups of the food you actually feed, using the energy value printed on the bag.
- Pet Food Price per 1,000 kcal CalculatorCompare two foods fairly by price per 1,000 calories instead of price per bag.
Keep reading
- Monthly Cost of a Dog: What People ForgetThe monthly cost of a dog beyond food: parasite control, vet care, insurance, grooming, daycare and replacements, with a template for annual bills.
- Dog Feeding Chart by Weight (Printable)A printable dog feeding chart by weight: daily calories for neutered, intact and inactive adults, with grams for 3,400, 3,600 and 3,800 kcal/kg foods.
- How Much Does It Cost to Own a Dog?Work out the real cost of owning a dog with your own numbers: one-off costs, monthly costs, first-year and lifetime totals, hidden extras and ways to plan.
- Pet Sitter vs Boarding: Cost ComparisonHow to compare boarding, drop-in visits and an overnight sitter: rate × nights, a 3 to 14 night table, extras, break-even rates and what price cannot tell you.