Use this BMR Calculator to estimate how many calories your body burns per day at rest. Enter your age, sex, height, and weight in either US units or metric units, then compare your BMR with an estimated daily calorie target.

BMR, or Basal Metabolic Rate, is the estimated number of calories your body burns each day while at complete rest. In other words, it is the energy your body needs to keep essential functions running, such as breathing, blood circulation, body temperature regulation, brain activity, cell repair, and organ function.

A BMR Calculator helps you estimate your resting calorie burn based on your age, sex, height, and weight. This number is useful when you want to understand your metabolism, estimate your daily calorie needs, or create a starting point for weight loss, weight gain, or maintenance calories.

This calculator is designed for both US units and metric units. If you live in the United States, you can enter your height in feet and inches and your weight in pounds. Metric users can switch to centimeters and kilograms.

Your BMR is not the same as the total number of calories you burn in a normal day. It only estimates the calories your body burns at rest. To estimate your full daily calorie needs, this calculator also applies an activity multiplier and shows your estimated TDEE, or Total Daily Energy Expenditure.

For example, if your BMR is 1,700 calories per day, your actual maintenance calories may be closer to 2,000–2,600 calories per day depending on your activity level. A desk worker, a recreational gym-goer, and a highly active athlete can have very different daily calorie needs even if their BMR is similar.

BMR is your estimated calorie burn at rest. TDEE is your estimated total daily calorie burn after adding movement, exercise, walking, work, and everyday activity. For practical weight management, TDEE is usually more useful than BMR because it is closer to your real maintenance calorie target.

This calculator includes two common BMR equations: the Mifflin-St Jeor equationand the Revised Harris-Benedict equation. The Mifflin-St Jeor formula is selected by default because it is widely used for modern calorie estimation. The Revised Harris-Benedict formula is also included for users who want to compare results with older fitness, nutrition, or weight loss calculators.

In this formula, W is weight in kilograms, H is height in centimeters, and A is age in years. If you enter pounds, feet, or inches, this calculator converts them internally before applying the formula.

Your BMR result is best used as a starting point, not as your final calorie target. For most people, the more practical number is the estimated TDEE shown in the result. From there, you can adjust calories based on your goal.

• Maintain weight: start near your estimated TDEE.
• Lose weight slowly: try a modest deficit, such as about 250 calories below TDEE.
• Lose weight more aggressively: a 500-calorie deficit is common, but it may not be appropriate for everyone.
• Gain weight gradually: try a small surplus, such as about 250 calories above TDEE.

After choosing a calorie target, track your body-weight trend for 2–4 weeks. If your weight is not changing in the expected direction, adjust your daily intake or activity gradually. Your real calorie needs can differ from calculator estimates because of muscle mass, sleep, dieting history, training intensity, medication, stress, and tracking accuracy.

Many BMR calculators only show one resting calorie number. This calculator is designed to be more useful for real calorie planning by combining BMR, TDEE, activity level, and goal-based calorie targets in one result.

• Supports both US units and metric units.
• Calculates BMR with Mifflin-St Jeor or Revised Harris-Benedict.
• Converts BMR into estimated TDEE using your activity level.
• Shows practical calorie targets for fat loss, maintenance, and lean weight gain.
• Optionally estimates a body-fat adjusted BMR when you enter your body fat percentage.