Inputs
Resting energy panelResting energy panel
Enter your age, sex, height, weight, and unit system to estimate BMR with two common formulas.
What this calculator helps you understand
What this calculator helps you understand
This BMR calculator helps you understand calories burned at rest before activity, training, or daily movement are added. It is the right first step when you want a simple answer to how many calories do I burn doing nothing, and it gives you the baseline that later tools such as the maintenance calories calculator and calorie calculator build on.
Use this BMR calculator to estimate calories burned at rest. It is a starting point for planning, not your full daily energy need.
BMR guide
What is BMR
Basal metabolic rate, or BMR, is the amount of energy your body uses to keep essential functions running while you are at rest. It is the baseline number behind many calorie planning tools, including BMR calculator pages and broader daily calorie estimates.
Comparison
Difference between BMR and TDEE
BMR only covers calories burned at rest. TDEE adds activity, training, and movement on top of that baseline. If you want the number that best matches a normal day, use TDEE; if you want the resting baseline first, start with BMR.
Formula
How BMR is calculated
This page compares two common equations: Mifflin-St Jeor and Harris-Benedict. They both use age, sex, height, and weight to estimate calories burned at rest, but they can produce slightly different answers because they were built from different datasets and assumptions.
Weight loss
Why BMR matters for weight loss
BMR matters because it shows the minimum resting energy your body uses before activity is added. That gives you a clearer starting point for maintenance calories, calorie deficits, and realistic plan changes instead of guessing from body weight alone.
Example
Example calculation
If you are 32 years old, weigh 68 kg, and stand 168 cm tall, the calculator estimates a resting calorie baseline and compares the Mifflin-St Jeor and Harris-Benedict formulas. That helps you see whether the formulas land close together and gives you a realistic starting point before you use a maintenance or calorie calculator.
- Enter your age, sex, height, and weight.
- Compare the two formula results.
- Use the resting number as the planning baseline.
Planning
Calories burned at rest vs daily needs
Calories burned at rest are not the same as the calories you need across a full day. Once movement, work, exercise, and normal activity are added, the total energy need is higher than the resting baseline.
Health context
How to increase metabolism safely
The most reliable ways to support a healthy metabolism are regular activity, strength training, enough protein, good sleep, and a sustainable calorie plan. Quick fixes rarely change the underlying energy balance in a lasting way.
Limitations
When BMR estimates are less reliable
BMR equations are helpful planning tools, but they are still estimates. Body composition, age, training load, and individual variation can all shift the real number, so the best use is as a starting point rather than a strict rule.
Comparison
Which calculator should you use?
Use BMI when you want a simple height-and-weight screen, lean body mass when you want a body composition view, waist-to-height ratio when you want a central fat screen, and maintenance calories when you want the daily eating target that follows from BMR.
Mistakes
Common mistakes when using BMR
The biggest mistakes are treating BMR like a full-day calorie target, using it as a diagnosis, or assuming one formula is exact for every person. The estimate works best when you treat it as a baseline and then compare it with activity and maintenance planning.