Everyone knows the numbers. A cat gets about half a cup of food a day. A dog gets a walk of about half an hour. These are not controversial figures. They are what the neighbor says, what the pet shop says, roughly what the bag says, and they are close enough to what most people actually do.
Both are wrong, and not by a rounding error. A neutered 10 lb indoor cat needs 209 kcal a day, which is closer to two ounces of kibble than half a cup, and 261 kcal if the same cat was never neutered. A Labrador needs 140 minutes of walking a day across two outings, and a young one in working condition needs 230. Six rules follow. Each one is stated the way people actually say it, then checked.
"The label knows how much your cat should eat"
The label knows how much food is in the food. It does not know your cat. Take one 10 lb adult at an ideal body condition, moderately active, and change exactly one answer at a time:
| The one thing that changed | Daily target | Against the baseline |
|---|---|---|
| Nothing, the baseline cat | 209 kcal | reference |
| Never neutered | 261 kcal | plus 52, a quarter more |
| Sleeps all day, no play | 178 kcal | minus 31 |
| Outdoor access, hunts | 251 kcal | plus 42 |
| Seven years old | 191 kcal | minus 18 |
| Past eleven | 174 kcal | minus 35, and three meals |
| Spread | 174 to 261 | 50% between the extremes |
Same animal, same scale reading, an 87 kcal spread. No label can carry that, because the label never asked. The one that catches most people is the neutering row: the requirement drops by a fifth the week of the surgery, the bowl does not, and nobody notices anything until the annual check two years later.
"Wet food is what makes cats fat"
Wet food is what makes the bowl look full. Those 209 kcal are the same 209 kcal however you serve them, and only the volume moves:
| Food | kcal per 100 g | What 209 kcal weighs | In the bowl |
|---|---|---|---|
| Wet, budget pate | 70 | 299 g | about three and a half 3 oz cans |
| Wet, typical | 85 | 246 g | just under three cans |
| Wet, high protein | 100 | 209 g | two and a half cans |
| Dry, economy | 330 | 63 g | a little over half a measuring cup |
| Dry, typical | 360 | 58 g | about half a cup |
| Dry, high protein | 420 | 50 g | under half a cup |
Six ways to serve one day of food, and the heaviest option weighs six times the lightest. That is not a difference in nutrition, it is a difference in water. What genuinely does put weight on cats is hiding in the last two rows: those two kibbles differ by 50 kcal in the same half cup, roughly a quarter of a small cat's entire day, and the cup does not know which bag it is scooping from. A three dollar kitchen scale removes the whole problem.
Worth checking your own animal rather than this one: a 6 lb cat, a 9 lb cat, a 12 lb cat and a 20 lb cat all land in different places.
"Fourteen pounds is a normal weight for a cat"
Fourteen pounds is a lean male Maine Coon, whose published range runs 13.2 to 22.0 lb. Fourteen pounds is also a severely obese male Siamese, whose range is 7.7 to 11.0 lb. Same number, two animals, opposite verdicts, and no chart can settle it because frame size inside a single breed varies by nearly half again.
A male domestic shorthair sits at 8.4 to 12.1 lb and a female at 6.6 to 9.9 lb, a gap that catches people out constantly: males run 20 to 40% heavier than females of the same breed, and reading a female against a male range is the most common way to decide a perfectly healthy cat is underweight.
What actually settles it is your hands. Ribs that feel like the back of your hand under a thin cover, a waist visible from above, a belly that tucks up rather than hanging straight. That is an ideal score. Ribs that feel like your palm are not.
"A fat cat needs a month of eating a lot less"
A month is not the unit. Take a 15 lb male domestic shorthair scored as obese. The target weight comes out at 11.1 lb, so there are 3.9 lb to lose. The safe rate is 1 to 2% of body weight per week, which for this cat is 0.15 lb. That is 26 weeks. Six months, not one.
The reason the rate matters more than the target is a condition called hepatic lipidosis. Cats mobilize fat to the liver faster than the liver can process it, and a few days of severe restriction, or of a cat simply refusing an unfamiliar diet food, can be enough to trigger it. This is the one number in feline nutrition worth being timid about.
There is a neat cross-check hiding in this example. Feeding an 11.1 lb cat at maintenance works out at 226 kcal a day. The calorie tool, working from the cat as it is today at 15 lb with an obese body condition, sets 206 kcal. The 9% gap between those two figures is the deficit itself. You feed the cat you have, aiming at the cat you want.
"A puppy needs a long walk to burn the energy off"
A puppy needs more walks, not longer ones. The working ceiling is five minutes per month of age, per walk, and it is a ceiling rather than a target:
| Age | One walk | Outings a day | Against a habitual half hour |
|---|---|---|---|
| 2 months | 10 min | 4 | three times the limit |
| 3 months | 15 min | 4 | double the limit |
| 4 months | 20 min | 4 | still over |
| 6 months | 30 min | 3 | finally matches |
| 9 months | 45 min | 3 | now under |
| 12 months | 60 min | 3 | half of what is needed |
The habitual half hour is wrong at both ends of that table, in opposite directions, which is a good sign that it was never a considered figure in the first place. Growth plates stay open until roughly 12 to 18 months in most dogs and up to 24 in giant breeds, and repeated long walks on hard ground inside that window are associated with joint problems later. Free play on grass is a different thing and far less of a concern.
"Half an hour a day is a decent walk"
For which dog, in what weather? A large adult in comfortable conditions comes out at 70 minutes per walk, twice a day, 3.3 miles at 2.8 mph. That is 140 minutes daily, four and a half times the habit.
And that is the mild case. Change one answer at a time again:
| The dog and the day | One walk | Per day | What the half hour does |
|---|---|---|---|
| Large adult, cloudy, 59 F | 70 min | 140 min | delivers a fifth of it |
| Small adult, cloudy, 59 F | 35 min | 105 min | small does not mean low need |
| Young large dog, hard condition | 115 min | 230 min | this is the sofa chewer |
| Large senior, cloudy, 59 F | 45 min | 135 min | shorter walks, one more of them |
| Flat faced dog, sunny, 86 F | 15 min | 45 min | here the habit is the danger |
That last row is the one that changes behavior. A pug at 86 F in the sun gets 15 minutes, three times a day, before 8 in the morning and after 8 in the evening. A long nosed dog of exactly the same size gets 25 minutes in the same conditions, and a Labrador gets 50. Flat faced dogs cool themselves by panting with far less surface to do it on, and above 95 F the ratio widens: 5 minutes against 10 for the same small dog with a normal muzzle.
The other half of that row is the ground. Asphalt reaches around 140 F when the air is at 86 F. If the back of your hand cannot stay on it for five seconds, neither can a paw.
The one that sounds wrong and is true
Here is a rule that gets corrected constantly and should not be. People say kittens eat more than adult cats, someone points out that they are a quarter of the size, and the kitten owner backs down.
The kitten owner was right. A 4 lb kitten between four and twelve months needs 263 kcal a day. The 10 lb adult from the top of this article needs 209. The growth multiplier is 2.0 against 1.2 for maintenance, and it more than cancels the difference in body weight. A kitten at less than half the size genuinely outeats the adult, and its resting requirement is only 109 kcal, so almost everything on that plate is being spent on growing.
What all six have in common
Not one of these rules is stupid. Half a cup and half an hour are reasonable averages of something, and if you picked a household at random the numbers would not be absurd. The problem is that they are stated as constants when every single one is the output of a calculation nobody ran, and the inputs that move them most are the ones people never think to mention: whether the animal is neutered, what its body condition actually is, how hot it is outside, and whether the breed can breathe properly in that heat. Weigh the animal, score it with your hands, look at the thermometer, and then pick a number. It will not be half a cup, and it will not be half an hour.
Tools discussed in this article
Cat Calorie Calculator - turns body weight, life stage, body condition, activity, neuter status and reproductive state into a daily kcal target, then converts it into ounces of wet or dry food and splits it across meals.
Dog Walk Calculator - works out how long to walk a dog today from breed size, age band, fitness and the weather outside, and returns minutes per walk, walks per day, distance and the safest time of day.
Cat Ideal Weight Calculator - turns a body condition score into a target weight in pounds, checks it against published breed ranges, and sets the safe weekly rate of change and how many weeks it should take.
More pets tools
Dog Calorie Calculator - the same resting energy method applied to dogs, where breed size moves the life stage thresholds. Worked through for a 40 lb dog and a 70 lb dog.
Pet Feeding Calculator - daily portions in grams and ounces with the monthly food bill, for a 10 lb cat or a 50 lb dog.
Cat Activity Calculator - the play minutes an indoor cat needs each day, split into hunting sessions and calm exploration. The other half of the energy balance from the first rule above.
Pet Water Calculator - how much a dog or cat should drink once the moisture in the food is subtracted, which changes sharply between the wet and dry rows of the second table.
Pet Age Calculator - whether your animal has crossed into the senior band yet, the answer that moved the cat from 209 to 191 kcal. Common cases: a 7 year old cat and a 10 year old dog.
Dog Elimination Diet Calculator - builds a food trial for a dog with a suspected food allergy: novel protein shortlist, trial ration and how many weeks the strict phase has to run.
More cat calorie cases: a 10 lb cat and a 15 lb cat.