How many calories should a dog eat to lose weight?
A dog that should weigh 20 kg (44 lb) is fed about 662 kcal a day to lose weight: the resting energy requirement of the target weight (AAHA 2021), 26% below what an inactive adult of that weight eats, whatever the dog weighs today. The tables give the diet calories by target weight, the grams of a weight-loss food that deliver them, and how many weeks a plan takes at the safe 1-2% of body weight a week.
Diet calories by target weight
The target is the weight the dog should be, not the weight it is: ask the vet, or use body condition (ribs easy to feel under a thin layer of fat, a waist seen from above). The diet line is the resting energy requirement of that weight, 70 x kg^0.75, and sits 26% below the inactive adult line at every weight. The last two columns are what the dog will eat once it gets there.
| Target weight | Weight-loss diet | Inactive adult at target | Active adult at target |
|---|---|---|---|
| 5 kg (11 lb) | 234 | 318 | 435 |
| 10 kg (22 lb) | 394 | 534 | 731 |
| 15 kg (33 lb) | 534 | 724 | 991 |
| 20 kg (44 lb) | 662 | 898 | 1,229 |
| 25 kg (55 lb) | 783 | 1,062 | 1,453 |
| 30 kg (66 lb) | 897 | 1,218 | 1,666 |
| 40 kg (88 lb) | 1,113 | 1,511 | 2,068 |
How long a plan takes
AAHA 2021 targets 1-2% of body weight a week. The percentage is of the current weight, so the kilograms lost each week shrink as the dog does and the weeks compound: a 25 to 20 kg plan that looks like 20 weeks at a quarter kilo a week takes 22.
| Plan | Diet kcal a day | Loss a week (1-2%) | Weeks at 1% | Weeks at 2% |
|---|---|---|---|---|
| 7 kg to 5.5 kg | 251 | 0.07-0.14 kg | 24 | 12 |
| 12 kg to 10 kg | 394 | 0.12-0.24 kg | 18 | 9 |
| 18 kg to 15 kg | 534 | 0.18-0.36 kg | 18 | 9 |
| 25 kg to 20 kg | 662 | 0.25-0.5 kg | 22 | 11 |
| 35 kg to 30 kg | 897 | 0.35-0.7 kg | 15 | 8 |
| 45 kg to 38 kg | 1,071 | 0.45-0.9 kg | 17 | 8 |
Grams of weight-loss food a day
Weight-loss foods are less energy dense than maintenance kibble (often 3,200-3,600 kcal/kg against 3,600-4,000), so the grams look like a normal portion while the calories do not. Read the kcal per kg on the bag, pick the column, weigh it, and split it into two or three meals.
| Target weight | 3,200 kcal/kg | 3,400 kcal/kg | 3,600 kcal/kg |
|---|---|---|---|
| 5 kg (11 lb) | 73 | 69 | 65 |
| 10 kg (22 lb) | 123 | 116 | 109 |
| 15 kg (33 lb) | 167 | 157 | 148 |
| 20 kg (44 lb) | 207 | 195 | 184 |
| 25 kg (55 lb) | 245 | 230 | 217 |
| 30 kg (66 lb) | 280 | 264 | 249 |
| 40 kg (88 lb) | 348 | 327 | 309 |
Running the plan
Weigh the dog and set the target with the vet first: a very heavy dog, an older one, or one that gained weight without eating more needs blood work before a diet. Feed by grams on a kitchen scale, not cups; take treats out of the ration; weigh every two weeks and adjust by 5-10% if the line is flat. At the target, move to the inactive adult line for that weight in how much should I feed my dog, or let the dog food calculator do it with the numbers from your own bag.
Frequently asked questions
- How many calories should a 30 kg dog eat to lose weight?
- If its ideal weight is 25 kg (55 lb): 783 kcal a day, the resting requirement of 25 kg, against the 1,218 an inactive 30 kg adult needs. At 1% of body weight a week the 5 kg comes off in about 18 weeks.
- How fast should a dog lose weight?
- 1-2% of body weight a week (AAHA 2021): 0.25-0.5 kg a week for a 25 kg dog. Faster than 2% costs muscle as well as fat. A 25 to 20 kg plan takes about 22 weeks at 1% and 11 at 2%; expect the slower end.
- Can I just feed less of the normal food?
- For a dog that is only slightly heavy, a small cut of the same food works. The diet line is a quarter below the inactive adult line, and cutting a maintenance food by that much cuts its protein, vitamins and minerals by the same share, which is why weight-loss foods fit the full nutrient amounts into fewer calories and add fibre so the dog feels fed.
- Do treats count?
- Yes, every one. Keep treats under 10% of the day's calories and take them out of the ration: on a 662 kcal plan that is 66 kcal, a handful of the dog's own kibble set aside in the morning, not a dental chew on top.
- What if the weight is not moving?
- Weigh on the same scale every two weeks. If nothing has changed after four weeks, cut the calories by a further 5-10% and recheck; if the dog is eating what the table says and still not losing, see the vet, because hypothyroidism and some medicines block weight loss.
More guides
- How many cups of dog food per day?
Cups of kibble a day by dog weight from the calories on your bag: tables for 300 to 450 kcal per cup, inactive and active adults, and meals.
- How much should I feed my dog? Grams and cups by weight
Daily calories and grams of dry food for dogs from 2 to 50 kg, inactive and active, on foods from 3,400 to 4,000 kcal/kg, with the WSAVA chart range.
- How many calories does a dog need per day?
Calories a day by weight and life stage from the NRC 2006 equations behind the WSAVA charts: adults 2 to 60 kg, puppies by adult size, weight loss.
- Puppy feeding chart: calories and cups by adult weight
Calories and cups a day for puppies at a quarter, half and three quarters of adult weight, for adult sizes 5 to 40 kg, with meals per day by age.
Sources
- NRC 2006, Nutrient Requirements of Dogs and Cats — adult, puppy and kitten energy equations
- WSAVA, Calorie Needs for Healthy Adult Dogs (July 2020) — chart range for dogs
- WSAVA, Calorie Needs for Healthy Adult Cats (July 2020) — chart range for cats
- AAHA 2021 Nutrition and Weight Management Guidelines — weight loss at the resting requirement of the target weight
Published 2026-09-17, last updated 2026-09-17. Figures are starting points from the published equations: individual animals vary by up to 30%, so adjust by body condition and ask your vet for puppies under 8 weeks, pregnancy, lactation or any illness.