BMR Calculator
Estimate resting calorie needs before adding activity.
Estimate resting calories from basic measurements
Basal metabolic rate is the estimated number of calories your body uses at rest before exercise and normal movement are added. This calculator uses the Mifflin St Jeor equation, a common modern estimate based on weight, height, age, and sex.
For example, a 35 year old male at 180 pounds and 70 inches estimates near 1,760 calories per day at rest. A 35 year old female with the same height and weight estimates lower because the equation uses a different constant.
Use BMR as the baseline, not the plan
The method converts pounds and inches to kilograms and centimeters, then applies the equation. BMR is not a measured lab result and should not be treated as a diet prescription. It is best used as the first step before choosing an activity factor in a TDEE estimate. Inputs stay on this page. That separation helps keep resting needs distinct from maintenance calories and workout burn estimates.
Frequently Asked Questions
Which BMR equation does this use?
It uses the Mifflin St Jeor equation: 10 times kilograms plus 6.25 times centimeters minus 5 times age, with a sex-specific constant.
Is BMR the same as daily calorie needs?
No. BMR estimates resting energy use before activity, digestion, work, exercise, and day-to-day movement are added.
Why can two people with the same weight get different BMRs?
Age, height, and the selected equation constant change the estimate, and real metabolism can still differ from the formula.
Is this private?
Yes. The page calculates locally in your browser and does not upload your personal inputs.
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