What this calculator does
Feeding by percentage of body weight is the standard approach for raw and fresh diets. An adult dog at a healthy weight eats around 2.5% of its body weight a day, an active working dog about 3%, and a young puppy as much as 8% while it is growing fastest.
The percentage falls steeply with age, which is the part worth understanding. A puppy at 8% is eating more than three times what the same dog will eat as an adult at 2.5%, and continuing puppy portions past the growth phase is a straightforward route to an overweight dog.
The formula
Body weight is multiplied by the feeding percentage for the life stage selected. The result is given in grams and ounces, halved for twice-daily feeding, and shown as a percentage of body weight so the basis is visible. These percentages suit fresh and raw diets; commercial dry food is far more calorie-dense and should be measured against the packet or calculated from calories instead.
| Term | Meaning |
|---|---|
| Percentage feeding | Daily food as a share of body weight, the standard method for raw and fresh diets. |
| Growth requirement | The elevated intake a puppy needs, falling from about 8% at under four months to about 3% by a year. |
| Maintenance | Around 2.5% for an adult at a healthy weight and normal activity. |
The inputs explained
| Field | What to enter |
|---|---|
| Body weight (kg) | Body weight in kilograms. For weight loss, use the target weight rather than the current one. |
| Life stage | Life stage and activity. The percentage falls sharply as a puppy grows, so this needs updating as the dog ages. |
When to use it
Portioning a raw or fresh diet
Percentage of body weight is how these diets are normally specified, and the calculation turns that into grams to weigh out.
Adjusting as a puppy grows
The requirement changes both because the dog gets heavier and because the percentage falls, and the two move in opposite directions, so it needs recalculating every couple of months.
Feeding for weight loss
The reduced percentage is calculated against target weight, and any deliberate weight-loss plan is worth setting with a vet rather than alone.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How much food does each life stage need?
The same 20 kg dog at each of the feeding percentages.
| Life stage | Daily food amount | Per meal, fed twice daily | As a share of body weight |
|---|---|---|---|
| Puppy, 0–4 months | 1,600 g/day | 800 g | 8.00% |
| Puppy, 4–8 months | 1,000 g/day | 500 g | 5.00% |
| Puppy 8–12 mths / active adult | 600 g/day | 300 g | 3.00% |
| Adult, ideal weight | 500 g/day | 250 g | 2.50% |
| Weight loss / less active | 300 g/day | 150 g | 1.50% |
Questions
Does this work for dry commercial food?
No, not directly. These percentages are for raw and fresh diets, which are mostly water. Dry kibble is far more calorie-dense, so feeding 2.5% of body weight in kibble would substantially overfeed. Use the packet guidance or work from calories instead.
How often should the amount be recalculated for a puppy?
Every few weeks while it is growing quickly. The dog is getting heavier, which pushes the amount up, while the percentage is falling, which pushes it down. The two partly cancel, and the only way to know the net effect is to redo the sum.
Should I feed once or twice a day?
Twice is the usual recommendation for adult dogs, and puppies need more frequent meals than that, typically three or four times a day when young. Large deep-chested breeds are often fed smaller meals more often because of bloat risk.
My dog is gaining weight on the calculated amount. What now?
Adjust downwards and keep watching, since these are starting estimates rather than prescriptions. Individual metabolism varies considerably. If weight is changing despite sensible feeding, that is worth a vet check rather than repeated cuts to the portion.
For a calorie-based figure that suits commercial food better, see the dog and cat calorie calculator. For daily water intake, see the dog water intake calculator.