🔥 BMR Calculator

Estimate your basal metabolic rate with proven formulas and see daily needs by activity level

Calculate Your BMR
Mifflin St Jeor, Revised Harris-Benedict, and Katch-McArdle (needs body fat %).

Used only for Katch-McArdle.

Your BMR
Basal Metabolic Rate
1705 kcal
Daily calorie needs based on activity level
Sedentary (little or no exercise)
× 1.2
2046 kcal
Light (1-3 days/week)
× 1.375
2344 kcal
Moderate (3-5 days/week)
× 1.55
2643 kcal
Active (6-7 days/week)
× 1.725
2941 kcal
Very Active (hard exercise daily)
× 1.9
3240 kcal
Extra Active (very hard exercise/physical job)
× 2
3410 kcal

Share Your Results

Formulas & Variables
Details for Mifflin St Jeor, Revised Harris-Benedict, and Katch-McArdle.
Mifflin St Jeor
For men:     BMR = 10W + 6.25H - 5A + 5 For women:   BMR = 10W + 6.25H - 5A - 161
Revised Harris-Benedict
For men:     BMR = 13.397W + 4.799H - 5.677A + 88.362 For women:   BMR = 9.247W  + 3.098H - 4.330A + 447.593
Katch-McArdle
BMR = 370 + 21.6 (1 - F) W
Variables
  • W: body weight in kg
  • H: body height in cm
  • A: age in years
  • F: body fat as a fraction (e.g., 20% → 0.20)

These match the equations used in our calculations and are commonly referenced for BMR estimation.

Quick examples

  • Male, 30 yrs, 180 cm, 75 kg, Mifflin St Jeor → switch Results to Calories and see BMR, plus TDEE by activity.
  • Female, 28 yrs, 165 cm, 60 kg, Harris-Benedict → compare BMR vs Mifflin by toggling the formula.
  • Male, 35 yrs, 178 cm, 82 kg, Katch-McArdle with body fat 18% → enter body fat to enable the formula.
  • Imperial units: switch to Imperial, 5 ft 6 in, 150 lb, age 40 → compute and then swap back to see converted metric.

Tip: Use the activity table to estimate daily calorie needs from your BMR.

Frequently Asked Questions

What is this calculator used for?

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How accurate are the results?

Our calculators use industry-standard formulas and algorithms to ensure high accuracy. However, for critical financial, medical, or legal decisions, we recommend consulting with a qualified professional.

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Free online BMR calculator. All calculations happen locally in your browser for privacy.