How much to feed a 6 lb dog: weight loss, food at 300 kcal per cup

Daily food

0.49cups a day

148 kcal for a 6 lb dog — weight loss, food at 300 kcal/cup

Daily calories	148kcal
Cups per dayat 300 kcal per cup	0.49cups
Twice a dayper meal	0.25cups
Three times a dayper meal	0.16cups
Resting energy (RER)70 × 2.7 kg^0.75 — what a dog burns doing nothing	148kcal
Activity multipliervet-supervised — RER of the TARGET weight	× 1
Body weight6 lb	2.7kg

Body weight: 6 lb
Life stage: weight loss
Food energy: 300 kcal/cup

The formula, and why the bag disagrees

Resting energy is not proportional to body weight. The veterinary formula is

RER = 70 × (weight in kg)0.75

That exponent is the whole story. A 6 lb dog needs 148 kcal at rest, and a working figure of 148 kcal a day once the ×1 multiplier for weight loss is applied — 0.49 cups at 300 kcal per cup.

Scaling in a straight line from a 20 lb dog would say 0.37 cups: 26% off. Feeding charts printed on bags interpolate linearly, which is why large dogs fed off the bag tend to end up heavy.

Check the calories on your bag

Dry food runs roughly 300 to 500 kcal per cup depending on brand and formula. The same "two cups" can therefore be a third more or less food than intended. The figure is on the bag, usually in small print near the guaranteed analysis, and it is the single most useful number on the packaging.

Meals

At 0.49 cups a day that is 0.25 cups twice a day, or 0.16 cups three times. Deep-chested breeds do better on smaller, more frequent meals.

Treats count, and they are the usual culprit

Treats should stay under 10% of the daily total — 15 kcal here. That is less than most people expect, and it is the common reason a carefully measured bowl still produces an overweight dog.

Where this page stops

This is arithmetic for a healthy adult dog, not medical advice. Puppies of large breeds, pregnant or nursing dogs, and any dog with kidney, heart, pancreatic or endocrine disease need a plan from a vet, and weight-loss diets should be supervised — dogs that lose weight too fast can develop serious liver problems.

Notes

Calories do not scale with weight. The exponent is 0.75, not 1 — a 6 lb dog needs 0.49 cups, but scaling straight up from a 20 lb dog would say 0.37 cups, 26% too little. Feeding charts printed on the bag usually interpolate in a straight line, which is why big dogs on them get overfed.
Check the kcal per cup on your bag. It ranges from about 300 to 500 across brands, so the same "two cups" can be a third more or less food. The figure is on the bag, usually in small print near the guaranteed analysis.
Weight loss belongs with a vet. This figure uses RER at ×1.0 and should be calculated from the TARGET weight, not the current one. Dogs losing weight too fast can develop serious liver problems, and the safe rate is 1–2% of body weight a week.
Healthy adult dogs only. Puppies of large breeds, pregnant or nursing dogs, and any dog with kidney, heart, pancreatic or endocrine disease need a plan from a vet — the calorie figure is the least important part of those diets.
Treats count. They should stay under 10% of the daily total, which is 15 kcal here — less than most people think, and the usual reason a carefully measured bowl still leads to a heavy dog.