BMR Calculator
Your BMR, basal metabolic rate, is what your body burns at rest. This calculator runs the exact Mifflin-St Jeor equation the Nouri app uses, and shows what your BMR becomes at every activity level.
| If your activity level is... | Your daily burn (TDEE) |
|---|---|
| Sedentary (x1.2) | – |
| Lightly active (x1.375) | – |
| Moderately active (x1.55) | – |
| Very active (x1.725) | – |
| Extremely active (x1.9) | – |
This is the exact first step Nouri runs when it builds your calorie target, and the app works it all out for you free. Same equation, same multipliers, published here in full. Get your numbers in Nouri free →
The exact equation this runs
Mifflin-St Jeor, published in the American Journal of Clinical Nutrition in 1990 and still the standard for healthy adults:
- Women: 10 x weight (kg) + 6.25 x height (cm) - 5 x age - 161
- Men: 10 x weight (kg) + 6.25 x height (cm) - 5 x age + 5
Two worked examples
- Woman, 30, 165 cm, 70 kg: 700 + 1,031.25 - 150 - 161 = 1,420 calories
- Man, 42, 180 cm, 95 kg: 950 + 1,125 - 210 + 5 = 1,870 calories
BMR is the foundation, not the target: nobody should eat at their BMR, because you burn well above it just living your day. Multiply by an activity factor for your true daily burn, which is what the table above previews and what the daily calorie needs calculator turns into a goal-adjusted target.
What moves your BMR
Weight is the biggest input (10 calories per kg in the equation), then height, then age pulling it down about 5 calories per year. Sex shifts the constant by 166 calories. That is why BMR drifts down as you lose weight and as you age, and why recomputing after meaningful change matters. What you cannot meaningfully change is the equation itself: metabolism-boosting tricks live in marketing, not in the arithmetic. The deeper tour of what is inside your daily burn is in TDEE Explained.
FAQ
What is BMR?
Basal metabolic rate: the calories your body burns at complete rest keeping you alive, organs, brain, temperature. For most people it is the largest share of daily burn.
Is this the same BMR Nouri calculates?
Yes, the identical Mifflin-St Jeor equation the app runs as step one of building your calorie target, published here with nothing changed.
Should I eat at my BMR to lose weight?
No. Your real daily burn is BMR times an activity factor, so eating at BMR is usually a much harsher deficit than intended. Set targets from TDEE instead.
What is the difference between BMR and TDEE?
BMR is rest-only; TDEE adds movement and digestion via the 1.2 to 1.9 multipliers. Targets are built from TDEE, with BMR as the foundation.
How accurate is a BMR calculator?
It is a population-average equation, good enough to start. Your logged intake against your scale trend over two weeks reveals your true numbers better than any formula.
Why is my BMR lower than my friend's?
The equation inputs: weight, height, age, and sex. Bigger, taller, younger, and male all push the number up; none of it reflects effort or willpower.
Does muscle increase BMR?
Body composition is not an input to this equation, which is one of its known simplifications. In practice, more muscle nudges real resting burn upward, another reason to keep protein high while dieting.
Can I speed up my metabolism?
Meaningfully, through the inputs you control: build muscle, move more (which raises the multiplier, not BMR). Products promising metabolic magic do not change this arithmetic.