A Jumbo Economy 4.5kg bag of HDB contains 90 half-cup servings, which will get you about:
⭐️ 6 months' breakfast for a small dog
⭐️ 4 months for a medium dog
⭐️ 3 months-ish for a large dog
But you'll understand that needs and appetites vary dramatically—even between dogs of the same weight. It's a matter of finding the right balance for their activity level, size and metabolism (just don't let those wiggles and eyes talk you into giving them too much!). Here's a few examples from our own lovely doggo's: