Calorie Calculator
Estimate adult BMR and maintenance calories from age, sex, height, weight and activity level using a named formula and transparent activity multipliers.
Enter or adjust the values above, then calculate.
Calories ↔ Kilojoules Converter
Quickly convert food energy between kilocalories (kcal), kilojoules (kJ), calories (cal) and joules (J), or open the full Calorie Converter for a dedicated conversion page.
Estimate maintenance calories from your profile and activity level
Estimate adult BMR and maintenance calories from age, sex, height, weight and activity level using a named formula and transparent activity multipliers.
Inputs this tool uses
- Age
- Sex used by the formula
- Height
- Weight
- Activity level
What you get
Estimated daily maintenance energy from Mifflin–St Jeor BMR × activity factor.
How to use the Calorie Calculator
- Enter age, sex used by the formula, height and the other fields relevant to this calculation.
- Select any method, activity level or option shown on this page, then choose Calculate.
- Read the main result together with the supporting values, method, assumptions and limitations below before using the estimate.
How this calculation works
Mifflin–St Jeor estimates resting energy from age, sex, height and weight. TDEE multiplies an estimated resting-energy value by a transparent activity factor. Activity factors are heuristics, not measurements.
Example calculation
The sample values loaded into the calculator produce 2250 kcal/day. This example exists to show how the output is structured; replace the sample values with your own inputs for your calculation.
Assumptions and limitations
- Energy and nutrient outputs are estimates or general reference values, not individualized treatment targets.
- Adult calorie-goal tools should not be used for children, pregnancy or medical nutrition therapy unless the page explicitly supports that life stage.
Sources and review status
Source set last verified 2026-09-25. No clinician review is claimed unless a real named reviewer is displayed.
Questions people ask about Calorie Calculator
Are maintenance calories the same as TDEE?
For planning purposes, maintenance calories are commonly estimated from total daily energy expenditure. This calculator estimates BMR first and then applies the activity factor you select.
Can I convert Calories to kilojoules here?
Yes. The calorie page includes a kcal/food Calories, kilojoules, calories and joules converter below the main calculator.
Connected tools
Continue with the closest related calculation without re-entering sensitive values automatically.
Estimate basal/resting energy with Mifflin-St Jeor and optionally compare established equations.
Open tool →◐RMR CalculatorEstimate resting energy needs and explain the practical distinction between RMR and BMR.
Open tool →◐TDEE CalculatorEstimate total daily energy expenditure from BMR and a clearly described activity multiplier.
Open tool →