Estimate adult maintenance calories, resting expenditure and guarded goal intake with Mifflin, revised Harris–Benedict or Katch–McArdle equations.
01 / DAILY ENERGY
Start with adult measurements and your usual activity. Example values are editable. Maintenance is an equation estimate, not a measured energy requirement.
02 / YOUR ESTIMATE
Calculate to see maintenance calories and compare guarded weight-loss and weight-gain planning scenarios.
03 / IMPORTANT CONTEXT
Population equations and conventional activity multipliers are estimates, not measured metabolism. Activity adjustment combines movement, daily living and food-related expenditure; it is not an independently measured exercise or digestion allocation. Pregnancy, breastfeeding, growth, illness, eating-disorder recovery and other individual circumstances need qualified guidance.
Do not add gross exercise calories to an activity-adjusted daily estimate without accounting for overlap. No weight-change rate or medical outcome is predicted. All calculations stay in your browser.
Enter your values locally; no inputs are uploaded.
Check validation feedback before reviewing the browser-generated result.
Review the explanation, copy supported outputs or reset the workspace.
Enter adult measurements and activity, select a planning goal and calculate. Advanced settings change the equation and adjustment; review assumptions before using an estimate.
Beginner-friendly controls, optional advanced settings, transparent estimates and private browser-local calculation.
Inputs are processed locally in your browser; no photos, uploads or personal profiles are required.
A resting energy equation is multiplied by a conventional activity factor: 1.2, 1.375, 1.55, 1.725 or 1.9. This estimates total daily energy expenditure, not a measured requirement. The activity adjustment combines multiple daily energy demands and is not a precise exercise allocation.
Mifflin–St Jeor is the default. Revised Harris–Benedict (1984) is optional. Katch–McArdle uses fat-free mass and requires measured body-fat percentage; missing body fat is never guessed. Optional comparisons use the same inputs and activity factor.
Mifflin and Harris were developed with different male/female coefficients. This parameter chooses an equation coefficient, not a gender-identity classification. Katch uses lean mass rather than a sex coefficient. Individual physiology may differ substantially from population averages.
Conservative software guardrails withhold adjustments above 500 kcal/day or 20% of estimated maintenance, and all intake targets below 1,500 kcal/day. Loss targets are also withheld below resting expenditure or at calculated BMI below 18.5. These limits are not universal nutritional minimums or personalized safe deficits; the maintenance number remains an equation estimate rather than a prescription.
Yes. One nutritional Calorie is one kilocalorie (kcal). This tool uses the thermochemical definition, 1 kcal = 4.184 kJ. Metric and imperial measurements are converted before the same equations are applied.
These general-adult estimates do not account for pregnancy, breastfeeding, growth, illness, recovery, eating disorders, unusual training demands or medication effects. A selected individualized-guidance flag withholds the goal intake. No weight-change rate or medical outcome is guaranteed.