BMR Calculator

Use this free BMR calculator to find your Basal Metabolic Rate using the Mifflin-St Jeor equation.
About BMR

Basal Metabolic Rate (BMR) is the number of calories your body needs to accomplish its most basic (basal) life-sustaining functions.

What BMR measures:

  • Breathing
  • Circulation
  • Cell production
  • Nutrient processing
  • Protein synthesis
  • Ion transport

Activity Levels:

  • Sedentary: Little or no exercise, desk job
  • Light Exercise: Sports 1-3 days/week
  • Moderate Exercise: Sports 3-5 days/week
  • Active: Hard exercise 6-7 days/week
  • Very Active: Very hard exercise & physical job

This calculator uses the Mifflin-St Jeor Equation, which is considered more accurate than the Harris-Benedict Equation for most people.

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How our BMR calculator works

1

Enter your stats

Type your age, sex, weight, and height. We use the Mifflin-St Jeor equation, which is the most accurate BMR formula for most non-athletic adults.

2

Get your basal metabolic rate

BMR is the calories your body burns at complete rest to maintain breathing, circulation, cell production, and brain function. It excludes any activity.

3

Add activity to get TDEE

BMR alone underestimates total calorie needs. Multiply by 1.2 (sedentary) to 1.9 (very active) to get TDEE, your true daily calorie burn.

Key things to know about our bmr calculator:

  • Average BMR: Adult women typically have a BMR of 1,200-1,500 calories. Adult men: 1,500-1,800. Higher for younger, larger, more muscular people.
  • Why BMR matters: Eating below BMR is essentially a starvation diet. Use BMR as a floor, then layer activity on top to find your sustainable intake.
  • Pair with TDEE: For activity-adjusted calorie needs, use the TDEE calculator. For weight loss targets, use the calorie deficit calculator.

For related calculations, try our TDEE calculator.