Calorie & BMR Calculator
Estimate adult resting energy expenditure (REE) and daily expenditure using an activity factor. Explore the formula and assumptions; this is not a diet prescription.
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Calorie & BMR Calculator
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How to use
- 1
Enter your details
Select your sex and enter your age, height and weight.
- 2
Choose activity level
Pick one of five levels that matches how often you exercise.
- 3
Check the results
Estimated resting and daily expenditure appear. These are not prescribed intakes.
Features
- Estimates REE and daily energy expenditure
- Uses the Mifflin-St Jeor prediction equation
- Compare estimates using different activity factors
- Your details are never sent to a server
Use cases
Study the equation
Change assumptions and compare the arithmetic.
Check input units
Use kilograms, centimetres and age in years.
See the effect of exercise
Change the activity level to see how exercise habits affect your burn.
Details
This equation estimates resting energy expenditure (REE), which differs from BMR in measurement conditions. Neither is a safe minimum intake.
This tool estimates REE with the Mifflin-St Jeor equation and multiplies it by an activity level to estimate total daily energy expenditure (TDEE). Choose from five activity levels, from sedentary to very active.
These adult estimates are not for setting intake for children, pregnancy, breastfeeding or medical treatment. Body composition and health can change actual expenditure. Consult a qualified health professional for individual dietary advice.
FAQ
What is basal metabolic rate?
BMR is expenditure under basal conditions. This tool instead predicts REE, which uses different measurement conditions. Neither gives a safe intake threshold.
Which formula is used?
The Mifflin-St Jeor equation estimates REE from the original sex category, age, height and weight.
How accurate is the result?
Individual error cannot be determined from these inputs alone. Do not make major dietary changes solely to match the estimate.
Is my information saved anywhere?
No. Everything is calculated in your browser and nothing is stored or transmitted.
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Verified: Male equation at age 30, 175 cm, 70 kg, factor 1.375 (BMR 1,649 kcal/day, TDEE 2,267 kcal/day), 5 activity multipliers, range errors, and JA/EN display are covered by browser tests
Did you know?
One kilocalorie (kcal) is the energy needed to raise the temperature of 1 kg of water by 1°C.