How much to feed
How much should I feed a 120 lb dog?
Last updated 23 September 2026 · How we write and check this
Short answer
A 120 lb dog, about 54.4kg, typically needs around 590 to 615g of a standard dry food a day, almost always split into two or three meals. At this size, individual variation between dogs is larger than the general formula can fully capture, so treat the calculated number as a confirmed starting point to check with your vet rather than a fixed target.
The calculation
A 120 lb dog weighs about 54.4kg, giving a resting energy of around 1,401 kcal, and a typical neutered adult at normal activity needs close to 1.6 times that, about 2,240 kcal a day. At 350 to 400 kcal per 100g of dry food, that lands near 590 to 615g.
This is a large daily volume, and splitting it into at least two meals is standard practice for a dog this size.
Why individual variation is bigger here
General feeding formulas are built from population averages, and at the extreme end of dog sizes the spread between individual dogs' real metabolic needs tends to be wider than the formula's built in assumptions.
A vet who has weighed and assessed your dog in person is better placed to fine tune this figure than a generic calculation alone, especially for breeds with unusually high or low activity for their size.
Practical feeding at this size
Split the total into at least two, ideally three meals, and use a scale that reads accurately in hundreds of grams rather than a small kitchen scale meant for baking.
Track weight monthly at your vet clinic and adjust the daily total by about 10 percent at a time based on the trend, not a single reading. A vet who has weighed and assessed your dog in person over several visits is better placed to fine tune this figure than a generic calculation alone.
Key takeaways
- A 120 lb (54.4kg) dog typically needs about 590 to 615g of dry food a day.
- Individual variation is larger at this extreme size than the general formula fully captures.
- Involve your vet to fine tune the calculated figure for your specific dog.
- Split the total into at least two meals using a scale suited to larger gram amounts.