Why the feeding chart on the bag overfeeds your dog
By Josh · Reviewed and updated: 2026-09-18
The chart on the back of the bag is indexed to one variable: body weight. But the amount a dog actually needs depends on at least three things, and weight is only one of them. Take a single 10 kg adult dog on a single food, and work out what it needs across the ordinary range of neutering status and activity: the answer runs from about 173 g a day to 309 g a day. That is a 79% spread — and the bag gives you one number. This page is about what sits inside that number, and how to get yours.
What the chart is actually telling you
A bag chart is a table with two columns. On the left is a weight, usually in bands — "10–15 kg" or similar. On the right is an amount, usually in cups, and usually given as a range.
Weight is the only thing you are asked for, so weight is the only thing the chart can respond to. It has no field for whether the dog is neutered. It has no field for whether it sleeps all day or works. It cannot ask what life stage it is in. Whatever you write in the weight column, that is the whole of your input.
What that leaves out, measured
Our calculator uses your dog's weight, life stage, neutered status, activity level and the calorie content of the food. So the gap between what it gives and what the bag gives is measurable rather than rhetorical. Here is the same 10 kg adult dog on the same food (350 kcal per cup, 110 g per cup), across six ordinary combinations:
| Same 10 kg dog | Factor | Daily energy | Daily food |
|---|---|---|---|
| Neutered · low activity | × 1.4 | 551 kcal | 173 g |
| Neutered · typical | × 1.6 | 630 kcal | 198 g |
| Neutered · active | × 2.0 | 787 kcal | 247 g |
| Neutered · working | × 2.5 | 984 kcal | 309 g |
| Intact · typical | × 1.8 | 709 kcal | 223 g |
| Intact · working | × 2.5 | 984 kcal | 309 g |
The last two rows share a factor: at the working level, neutered and intact dogs are given the same multiplier. The workload dominates, and the difference in neutering status disappears inside it.
Every row in that table describes the same animal by weight. The chart on the bag would send all six of them to the same line. And the distance between the top and the bottom of that table is:
This is not a small-dog or a large-dog effect. Run the same six combinations for a 25 kg dog and the spread is 79% again, from 344 g to 615 g. The percentage does not shrink as the dog gets bigger, because the variables are multiplicative — they scale with the dog.
That 79% is the full span of the table, not a typical difference. How far any one dog sits from the bag's number depends on how far its real activity level sits from the one the chart assumes. The point is that the span exists — and only your own inputs can tell you where in it you land.
The three variables the chart cannot ask about
| Variable | Effect on the amount |
|---|---|
| Activity level | The largest of the three. On the 10 kg dog, going from low activity to working multiplies the amount by about 1.8×: 173 g becomes 309 g. A dog that spends the day on a sofa and a dog that spends it working are not eating for the same body. |
| Neutered or not | Worth about 13% at the same activity level: an intact 10 kg dog on a typical routine needs about 223 g where a neutered one needs 198 g. Read the other way round, the same relationship is roughly an 11% reduction after surgery — measured from the other end, which is the direction the neutering page works from. |
| Life stage | Larger than either, in the other direction. A puppy under four months needs roughly three times the resting energy of an adult, so a chart indexed to weight underestimates a growing dog badly — the puppy page covers that separately. |
Why the chart is built that way
It is worth being fair to the manufacturer here, because the obvious reading — that the chart is designed to sell more food — is not the main reason.
A bag has to carry one table for every dog that will ever open it. It cannot know whether your dog is neutered, and it cannot ask. Faced with that, the manufacturer has to pick a value that is safe across the whole population it will meet. And the two errors are not symmetrical:
- Feed too little and a dog loses weight visibly, and the owner notices quickly.
- Feed too much and the dog gains weight slowly, over months, in a way that is easy to normalise — and in most populations, overfeeding is far more common than underfeeding.
Two further facts make that clearer. There is no international standard for how feeding guides are calculated, and manufacturers make different assumptions — which is why two bags can recommend different amounts for the same dog. And the space on a label is finite, which limits how much a chart can ask about. A packaging chart is not a nutritional instrument so much as what fits on the pack.
So the number printed tends toward the upper half of the plausible range. It is less a recommendation than a ceiling that will not starve anybody. That is a defensible design decision for an anonymous bag — and it is exactly the wrong number for your dog, because your dog is not the average of every dog.
What to do instead
Two steps, and neither takes long:
- Get your own number. The calculator takes the four inputs the bag cannot ask for, and gives you a daily amount in grams. Bookmark it rather than re-deriving it.
- Then look at the bag. Not to follow it — to see the gap. If the bag says 250 g and your dog's number is 198 g, that difference is the reason the chart exists and the reason it is not for you.
Which direction the gap runs depends on one thing: whether your dog does more or less than the activity level the chart assumed. The printed figure sits toward the top of the plausible range — and that is the reasoning set out in the previous section, not a statistic about other people's dogs. So for a neutered dog on an ordinary indoor routine, the calculated amount tends to come out lower. For a working dog it can come out higher, and treating the calculation as "always less" would be the same error in the opposite direction.
The number is also a starting point rather than a fixed setting. Recheck it against the body condition score every few weeks, and change it when the dog changes — after neutering, after a season of harder exercise, or through the transition into older age.
Frequently asked questions
Is the feeding chart on the bag wrong?
Not wrong — incomplete. It uses body weight as its only input, so it cannot distinguish between a neutered lap dog and an intact working dog of the same size. Measured on the same 10 kg dog, those two can differ by around 79% in daily food. The chart is a general average; your dog is a specific case.
Why does my dog need less than the bag says?
Most likely because of activity. The printed figure tends toward the upper half of the plausible range, since a bag must be safe for every dog that opens it, and overfeeding is easier to miss than underfeeding. A neutered dog on a typical indoor routine sits near the lower end of the range.
How much difference does neutering actually make?
At the same activity level, about 13% on the amounts we calculated: an intact 10 kg dog on a typical routine needs roughly 223 g a day where a neutered one needs 198 g. It is a real difference, but a smaller one than activity level, which can move the same dog between 173 g and 309 g.
Should I just feed the middle of the range the bag gives?
It is better than the top of the range, but it is still a guess about your dog made from other dogs. Working out your own number takes four inputs and gives you a figure with a reason behind it, which is also the figure you can adjust later when something changes.
Work out your dog's daily amount in grams →
Check body condition, not just weight →
Recently neutered? The amount has to change →
Feeding amounts by weight, in a table →