What This Calculator Does
The Dog Food Bag Duration Calculator estimates how long a single bag of dry dog food (kibble) will last based on how much your dog eats each day. Knowing this helps you budget, time your reorders, and avoid running out of food unexpectedly. It works for any country and any brand because it relies only on the bag weight and your feeding amount.
How to Use It
Enter three values: the bag weight in kilograms (shown on the package), the number of cups of food you serve per day across all meals, and the grams per cup of your specific kibble. A standard 8 oz measuring cup of dry dog food typically weighs about 100–130 grams, but this varies by kibble size and density — check your bag or weigh a cup on a kitchen scale for the most accurate result.
The Formula Explained
First the calculator converts the bag weight to grams (1 kg = 1000 g). It then multiplies the cups fed per day by the grams per cup to find the daily food intake in grams. Finally it divides the total grams in the bag by the daily grams to get the number of days the bag will last:
$$\text{Days} = \frac{1000 \times \text{Bag Weight (kg)}}{\text{Cups Per Day} \times \text{Grams Per Cup}}$$
The result is also shown in weeks (days ÷ 7) and months (days ÷ 30.44).
Worked Example
Suppose you buy a 15 kg bag and feed your dog 2 cups per day, with each cup weighing 120 g. Daily intake = \(2 \times 120 = 240\) g. The bag holds \(15 \times 1000 = 15{,}000\) g. So \(15{,}000 \div 240 = 62.5\) days — roughly 8.9 weeks or about 2 months per bag.
FAQ
How many grams is one cup of dog food? Most dry kibble runs 100–130 g per 8 oz cup, but small or dense kibble can be higher. Weigh a cup for accuracy.
Can I use pounds instead of kilograms? This tool uses kilograms. Convert pounds to kg by dividing by 2.205 (e.g. 30 lb ≈ 13.6 kg).
Why does my bag run out faster than predicted? Treats, free feeding, spillage, and overfilled cups all add up. Measure portions precisely and account for treats.
