Calculate your Basal Metabolic Rate and Total Daily Energy Expenditure. Mifflin-St Jeor formula. Free, in your browser.
Why this matters
The Mifflin–St Jeor equation estimates resting energy expenditure from weight, height, age, and a sex-specific coefficient. It does not measure your metabolism. This page labels that estimate BMR, then multiplies it by a selected activity factor to illustrate TDEE.
This implementation does not calculate body-fat-based equations, macros, or prescribed calorie targets. Activity factors are broad modeling assumptions, not measurements of your exercise or a guarantee of accuracy. It is intended for adult reference calculations, not children's growth, pregnancy, or individualized medical nutrition.
Your Stats
Equation coefficient
Results
BMR
0
calories/day at rest
TDEE
0
maintenance calories
A reproducible equation example
At 70 kg, 175 cm, age 30, using the male coefficient: 700 + 1093.75 − 150 + 5 = 1648.75 kcal/day. With factor 1.375, the modeled TDEE is 2267.03125 kcal/day. The display rounds those estimates to 1649 and 2267.
Formula reference
Mifflin et al., A new predictive equation for resting energy expenditure in healthy individuals (1990), doi:10.1093/ajcn/51.2.241. This is a bibliographic reference, not a claim that this implementation or its activity factors have been clinically validated.
Frequently Asked Questions
What is BMR?
Basal Metabolic Rate is the number of calories your body burns at complete rest just to maintain basic functions (breathing, circulation, cell production). It does not include any activity.
What is TDEE?
Total Daily Energy Expenditure is BMR multiplied by an activity factor. It estimates how many calories you burn per day including activity. This is your maintenance level.
Which formula does this use?
Mifflin–St Jeor, using weight, height, age, and the selected male/female equation coefficient. No body-fat-based alternative is implemented.
How accurate is this?
It is a population-based estimate. The tool does not establish a personal error margin or measure energy needs. Activity-factor selection adds uncertainty; medical nutrition decisions need individual assessment.
