Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Cups per day
2.83
Cups per meal
1.42
Daily calories
1,076
Resting energy requirement
672
Food cost per day
$1.46
Food cost per month
$44.46
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter dog weight (lb).
- 2Enter life stage / activity.
- 3Enter calories per cup of food (kcal).
- 4Enter meals per day.
- 5Enter cost per bag ($).
- 6Enter bag weight (lb).
- 7Read your cups per day on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Feeding guidelines on the bag are averages for an intact adult dog at maintenance. This calculator starts from resting energy requirement (RER), applies a life-stage multiplier, and converts calories into cups using the kcal density printed on your specific food.
Worked example
Using the values the calculator loads with:
Inputs
- Dog weight: 45 lb
- Life stage / activity: Neutered adult, normal
- Calories per cup of food: 380 kcal
- Meals per day: 2
- Cost per bag: 62 $
- Bag weight: 30 lb
Results
- Cups per day: 2.83
- Cups per meal: 1.42
- Daily calories: 1,076
- Resting energy requirement: 672
- Food cost per day: $1.46
- Food cost per month: $44.46
What each field means
Inputs
- Dog weight (lb)
- The dog weight used in the calculation, measured in lb. Starts at 45 lb so you have a working example on load.
- Life stage / activity
- Pick the option that matches your situation — the maths changes per option. Choices: Weight loss (0.8–1.0×), Neutered adult, low activity, Neutered adult, normal, Intact adult / active, Working dog, Puppy under 4 months.
- Calories per cup of food (kcal)
- The calories per cup of food used in the calculation, measured in kcal. Starts at 380 kcal so you have a working example on load.
- Meals per day
- The meals per day used in the calculation. Starts at 2 so you have a working example on load. Accepted range: 1–6.
- Cost per bag ($)
- The cost per bag used in the calculation, measured in $. Starts at 62 $ so you have a working example on load.
- Bag weight (lb)
- The bag weight used in the calculation, measured in lb. Starts at 30 lb so you have a working example on load.
Results
- Cups per day
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Cups per meal
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Daily calories
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Resting energy requirement
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Food cost per day
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Food cost per month
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Where do I find calories per cup?
It is on the bag near the guaranteed analysis, usually written as 'kcal ME/cup'. Densities range from about 300 kcal for weight-control formulas to 500+ for performance foods, so using the real number matters more than the weight-based chart.
My dog needs to lose weight — what do I change?
Pick the weight-loss factor and run the calculation on the target weight, not the current weight. Re-weigh every two weeks and aim for 1–2% body weight lost per week.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Dog Food Portion Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/dog-food-portion
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/dog-food-portion" target="_blank" rel="noopener">Dog Food Portion Calculator — RevenueLab</a> (2026).</p>
Source: [Dog Food Portion Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/dog-food-portion) (2026).