How This Calculator Works
BMR turns the inputs into a visible formula-based estimate. Use it as an informational estimate and keep personal variation, routine changes, and non-medical context in mind.
Use the BMR calculator to estimate resting energy needs and a rough daily calorie target based on activity level.
The calculator uses the Mifflin-St Jeor equation and multiplies the result by your activity factor.
Formula
BMR = 10 x weight kg + 6.25 x height cm - 5 x age + sex adjustment. TDEE = BMR x activity.
Example Calculation
A 35-year-old, 70 kg, 170 cm female profile estimates about 1,430 kcal/day BMR before activity.
When to Use This Calculator
- Estimate maintenance calories
- Compare activity assumptions
- Support conversations with a qualified professional
Practical Scenarios
- Use the calculator to establish a rough baseline, then compare it with how your routine, body context, and goal actually feel in practice. Use case: Estimate maintenance calories.
- Rerun the estimate when activity, weight, sleep, training load, medication, or health status changes enough to move the inputs. Start with BMR, then compare the changed result with the original.
- Use related health and fitness calculators for context, not as a diagnosis or personal treatment plan. This is especially useful when you need to support conversations with a qualified professional.
Tips
- Activity multipliers are rough
- Do not use BMR as a diet prescription
- Health needs vary by person
Common Mistakes
- Treating BMR as total daily needs
- Using activity multipliers too aggressively
- Ignoring medical context
- Treating a population formula as a personal medical recommendation.
- Ignoring personal variation such as training status, body composition, medication, illness, or clinical history.
Assumptions and Limitations
The BMR Calculator is an informational estimate and should be interpreted with personal context rather than treated as a diagnosis or treatment plan. Review the formula, assumptions, and related calculators before using the result in a decision.
- Age, medical history, body composition, medication, training status, and personal context can change what the result means.
- The result is informational and is not medical advice, diagnosis, or treatment.
- Use health estimates as a starting point for discussion with a qualified professional when needed.
BMR keeps BMR, TDEE, calories and metabolism grounded in estimates, personal variation, and non-medical wording.