BMR Calculator
Basal Metabolic Rate using the Mifflin-St Jeor equation.
Formula: Mifflin-St Jeor: 10×kg + 6.25×cm − 5×age + (5 male / −161 female)
Worth Knowing
The Mifflin-St Jeor equation used here replaced the older Harris-Benedict formula in most clinical and fitness settings because it tends to estimate resting energy needs more accurately across a wider range of body types. Your BMR is the calorie floor your body needs just to keep functioning at complete rest — it deliberately excludes any movement, exercise, or daily activity, which is why it's almost never the number you should eat to, only the starting point before applying an activity multiplier (see our TDEE Calculator). Individual metabolism varies from the formula's prediction by roughly 10%, so treat the result as a solid estimate rather than an exact measurement.
How to Use
- Enter Gender into the first field of the BMR Calculator.
- Fill in the rest: Weight, Height, Age.
- Your result appears instantly as you type — there's no submit button or page reload.
Formula
Mifflin-St Jeor: 10×kg + 6.25×cm − 5×age + (5 male / −161 female)