BMR calculator
Enter your sex, age, height, and weight. We run the Mifflin-St Jeor equation and return your basal metabolic rate, the calories your body burns at rest. It is the first number in any weight-loss math.
How this calculator works
The calculator uses the Mifflin-St Jeor equation, the resting-metabolism formula dietitians reach for first. It converts your height and weight to metric, then runs one of two versions.
- Men. BMR equals 10 times weight in kilograms, plus 6.25 times height in centimeters, minus 5 times age, plus 5.
- Women. The same, minus 161 instead of plus 5.
The result is your resting burn in calories per day. It is not the number you eat. For that you need your total daily burn, which folds in movement.
BMR is the input, TDEE is the answer
BMR is what you would burn doing nothing. Real life adds walking, working, and exercise, so your actual daily burn is higher. That fuller number is your total daily energy expenditure (TDEE), and it is the one a weight-loss plan works from. Once you have it, the calorie-deficit calculator sets a daily target for the pace you want.
Where GLP-1s fit
GLP-1 medications do not speed up metabolism or raise your BMR. They cut appetite, which makes eating below your burn far easier to sustain. If your BMR and TDEE tell you a deficit is the goal, the next question is whether you meet the prescribing criteria. The BMI-to-program calculator answers that in one step.
Frequently asked questions
What is BMR?
Basal metabolic rate is the number of calories your body burns at complete rest in a day to keep basic functions running: breathing, circulation, cell repair, brain activity. It is the floor of your daily calorie burn, before any movement. For most adults it accounts for 60 to 70 percent of the calories they burn in a day.
BMR or TDEE, which number do I actually use?
TDEE. Your total daily energy expenditure is BMR plus the calories you burn moving, and it is the number a weight plan works from. BMR is the input; TDEE is what you eat around. Use the TDEE calculator next, then the calorie-deficit calculator to set a target.
Which formula does this use?
The Mifflin-St Jeor equation. It estimates resting energy expenditure more accurately than the older Harris-Benedict equation across the general adult population, which is why registered dietitians and obesity-medicine clinicians default to it. It uses sex, age, height, and weight.
Does a GLP-1 raise my BMR?
No. GLP-1 medications like Wegovy and Zepbound do not speed up your metabolism. They reduce appetite and slow stomach emptying, so you eat less and hold a calorie deficit more easily. Weight loss can slightly lower BMR (a smaller body burns fewer calories), which is one reason protein and resistance training matter during treatment.
How accurate is a BMR estimate?
An equation is a good estimate, not a lab measurement. Real BMR varies with muscle mass, genetics, and hormones, so two people with identical stats can differ by 5 to 10 percent. Treat the number as a starting point, track your weight over two or three weeks, and adjust.
Other calculators
- TDEE calculator: your full daily burn, resting plus activity.
- Calorie-deficit calculator: the daily target for each rate of loss.
- Protein calculator: the daily grams to protect muscle in a deficit.
- BMI-to-program calculator: your BMI and the programs you qualify for.
