What counts as a large breed for feeding purposes?

Most veterinary guidelines use an expected adult weight of roughly 25 kg (55 lb) or more as the threshold for large-breed puppy formula recommendations.

Can a small dog eat large-breed food?

Not ideally for puppies, since the calorie density and calcium/phosphorus levels are tuned for a different growth pattern. For adult dogs, the difference matters less, though kibble size may be impractical for a small dog.

Do medium breed dogs need a special formula?

Medium breeds can generally use either an all-life-stages formula or a size-matched one; their growth pattern falls between the small- and large-breed extremes and is less likely to require the same tight calcium/phosphorus control as large breeds.

Large Breed vs. Small Breed Dog Food: Why the Formula Matters | PetCalculator

Large and small breed dogs don't just need different amounts of food -- their formulas are built around genuinely different metabolic and skeletal needs. Here's the real comparison.