Health and nutrition calculators
These tools estimate an order of magnitude (energy expenditure, BMI, protein) from published formulas. They do not replace medical, dietetic or coaching advice.
Metabolism, body composition and fluid needs vary with age, illness, pregnancy, medicines and training. Pages name the formula, the original population when known, and what the number does not measure.
Most used
- BMI calculatorBody mass index is weight in kg divided by height in meters squared. Labels use adult WHO cut-offs. That is not an obesity diagnosis by itself, and it is not a child BMI.
- Calorie calculatorThree steps: Mifflin-St Jeor resting burn, times a lump activity factor, then a goal offset. The result is an estimate, not a diet.
- TDEE calculatorTDEE here is Mifflin-St Jeor resting metabolism times an activity factor. It includes no deficit, no surplus, and no 1,200 kcal floor.
- Basal metabolic rateTwo resting-energy equations: Mifflin-St Jeor as the main result, revised Harris-Benedict (1984) as a comparison. No activity factor is applied.
Subcategories
Energy and calories
BMR, TDEE, calorie target and macros.
Weight and composition
BMI, Navy body-fat estimate, reference weight.
Full list
- Calorie calculatorThree steps: Mifflin-St Jeor resting burn, times a lump activity factor, then a goal offset. The result is an estimate, not a diet.
- TDEE calculatorTDEE here is Mifflin-St Jeor resting metabolism times an activity factor. It includes no deficit, no surplus, and no 1,200 kcal floor.
- Basal metabolic rateTwo resting-energy equations: Mifflin-St Jeor as the main result, revised Harris-Benedict (1984) as a comparison. No activity factor is applied.
- Macro calculatorThe tool applies an energy percent to the calories you type, then converts with 4 kcal/g for protein and carbohydrate and 9 kcal/g for fat. These are templates, not a care plan.
- Protein calculatorThree coefficients per kilogram: the EFSA PRI 0.83 g/kg for a healthy adult, 1.2 g/kg as an internal “active” rung, 1.6 g/kg as an example in the middle of the 1.4–2.0 g/kg range often cited for training (ISSN 2017).
- BMI calculatorBody mass index is weight in kg divided by height in meters squared. Labels use adult WHO cut-offs. That is not an obesity diagnosis by itself, and it is not a child BMI.
- Body fat (Navy method)The percent comes from Hodgdon and Beckett (1984) circumference equations for the US Navy: logarithms and measurements converted to inches. It is a field estimate, not absorptiometry.
- Reference weightThe featured result is the kilogram interval that matches BMI 18.5 to 24.9 for your height. Devine, Robinson, and Miller are historical conventions, not a weight “to aim at.”
- Water intakeTwo distinct figures: a 35 ml per kilogram rule of thumb, optionally raised by an internal activity bonus, and the EFSA 2010 adequate intake (2.0 L/day women, 2.5 L/day men, water from drinks and foods). Neither is an order.
- Running pacePace is total time divided by distance. Average speed is the inverse. No calories are estimated: ACSM METs are not applied here.
Questions
Why several formulas for the same need?
No single equation describes everyone. Mifflin-St Jeor is often preferred for adult resting energy; revised Harris-Benedict is shown for comparison. The result remains an estimate.
Does BMI diagnose obesity?
WHO uses BMI as a population indicator. For one person it ignores muscle mass, fat distribution and many clinical situations. It is not a diagnosis.