BMR Calculator
Estimate basal metabolic rate from age, sex, height and weight using the Mifflin–St Jeor equation.
Calculator workspace
Enter your values, then calculate to see the result and supporting figures.
What Does Your BMR Result Mean?
Your BMR result is an estimate of the energy your body would use in about 24 hours at rest to support basic functions such as breathing, circulation and temperature regulation. For example, 1,760 kcal/day means an estimated resting energy use of about 1,760 kilocalories over a day. The Mifflin–St Jeor equation is technically a resting-energy estimate (REE/RMR), although it is commonly presented online as a BMR calculator.
It is not your maintenance-calorie target. Total daily energy expenditure is usually higher because movement, exercise and digestion add to resting energy use. For an activity-adjusted estimate, use the Maintenance Calories / TDEE Calculator.
How This BMR Calculator Works
Estimate basal metabolic rate from age, sex, height and weight using the Mifflin–St Jeor equation. The rebuilt page uses calculator-specific logic rather than the legacy page script. Inputs are validated before calculation, and supporting figures are shown with the headline result so the arithmetic is easier to check.
Core method: Male BMR = 10W + 6.25H − 5A + 5; female BMR = 10W + 6.25H − 5A − 161.
How to Use It
- Enter the values requested in the calculator workspace.
- Select Calculate and correct any input highlighted by validation.
- Review the main answer, supporting figures and formula/method shown with the result.
- Use Copy Result, Share Result or Save Result Image if you need to keep the calculation.
Worked Example
A 30-year-old, 70 kg, 170 cm male has an estimated BMR of about 1,618 kcal/day.
Common Uses
- Energy estimates
- Fitness planning
- Nutrition calculations
Common Search Questions About BMR Calculator
How do I calculate this?
Estimate basal metabolic rate from age, sex, height and weight using the Mifflin–St Jeor equation.
What formula does this calculator use?
Male BMR = 10W + 6.25H − 5A + 5; female BMR = 10W + 6.25H − 5A − 161.
How can I get the result quickly?
Enter the required values and select Calculate. The rebuilt mobile interface brings the result into view instead of leaving it far below the form.
Important Limitations
BMR is an estimate, not a medical measurement. Pregnancy, illness, medications, body composition and other factors can change energy needs. Consult a qualified professional for medical or nutrition decisions.
Frequently Asked Questions
Does the calculator upload my inputs?
No. The calculation runs in the browser and does not require an account.
Can I calculate again with different values?
Yes. Change any input and calculate again to compare scenarios.
Should I verify important results?
Yes. For high-impact financial, legal, health, engineering or contractual decisions, compare calculator output with current source information and appropriate professional guidance.