Basal Metabolic Rate Calculator

Calculate your Basal Metabolic Rate instantly for free and see how many calories your body needs at rest.

  • Free
  • No sign-up
  • Instant results

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How to use it

  1. Select your gender.
  2. Enter weight, height, and age.
  3. Click Calculate.
  4. View your BMR in kcal/day.

What it does – This tool applies the 1984 Revised Harris‑Benedict equation to turn your gender, weight, height, and age into a daily calorie estimate called Basal Metabolic Rate (BMR). Why it matters – BMR is the energy your body uses at complete rest; knowing it lets you set realistic calorie targets for weight loss, maintenance, or gain. How to read it – The result is shown in kilocalories per day (kcal/day). Use that number as the baseline, then adjust for activity level, diet goals, or medical advice. No signup, no ads, just an instant, free number you can trust for planning meals and workouts.

Pro tips

  • Round the result to the nearest whole number for meal planning.
  • If you’re very active, add an activity factor to the BMR.
  • Use metric units as entered; conversion errors cause inaccurate results.
  • Check that age and weight are realistic; extreme values skew the calculation.

Real-life examples

  • Planning a weight‑loss diet and need a calorie baseline.
  • A fitness coach setting macro targets for a client.
  • A medical professional assessing metabolic health for a patient.

Case study

Sarah, 32, entered her stats and saw a BMR of 1,420 kcal/day. She used that number to set a 500‑calorie deficit, lost 8 lb in six weeks, and felt more energetic.

Frequently asked questions

What is Basal Metabolic Rate?
BMR is the number of calories your body burns at rest to keep vital functions running.
Do I need to fast before using the calculator?
No, the calculation uses only gender, weight, height, and age, not recent food intake.
Can I use pounds and inches?
Convert to kilograms and centimeters first; the tool only accepts metric units.
How often should I recalculate?
Update whenever you gain or lose significant weight or if your age changes by several years.
Is the result a daily calorie target?
It’s a baseline; add activity multipliers to get a total daily energy expenditure for diet planning.