Portions are calories, not cups
What moves the number
Two dogs of the same weight can need meaningfully different portions. A young, intact, high-energy working dog burns far more than a middle-aged neutered couch companion of the same size.
Age matters - puppies need more calories per pound than adults, and seniors typically need fewer. Activity matters most of all: a dog that runs daily is a different feeding problem from one whose exercise is a stroll around the block.
This is why keeping your dog's profile up to date with the brand actually matters - a portion set for last year's activity level may not fit this year's.
Don't forget the treats
How to know the portion is right
The bowl is a terrible judge - fresh food is calorie-dense, so correct portions often look small next to a heap of kibble. Judge by the dog instead: body weight over weeks, and body condition you can feel - ribs palpable under a thin fat layer, a visible waist from above.
If your dog gains or loses noticeably on the calculated portion, update the profile or ask the brand's support to adjust, and loop in your vet for anything more than minor drift. For dogs with medical conditions, portion questions belong with your vet from the start.