Free Online Tool

BMR
Calculator

Calculate your Basal Metabolic Rate and daily calorie needs using the scientifically proven Mifflin-St Jeor equation. Free, instant results.

How BMR Calculation Works

Three key factors determine your metabolic rate

1

Enter Your Stats

Input your age, gender, weight, and height. Choose between metric and imperial units.

2

Select Activity Level

Choose your daily activity level from sedentary to extra active. This determines your TDEE multiplier.

3

Get Your Targets

Receive your BMR, TDEE, and personalized calorie targets for weight loss, maintenance, and weight gain.

Why Use Our BMR Calculator?

Scientifically accurate, beautifully designed

Mifflin-St Jeor Equation

Uses the most accurate BMR formula recommended by medical professionals worldwide.

TDEE Calculation

Automatically calculates your Total Daily Energy Expenditure based on your activity level.

Weight Loss Targets

Get personalized calorie targets for safe, sustainable weight loss of 0.5 kg per week.

Metric & Imperial

Switch between kg/cm and lbs/inches. Works with any unit system you prefer.

Instant Results

No waiting, no sign-ups. Get your BMR and calorie targets instantly, completely free.

For Everyone

Works for all ages, genders, and body types. Accurate results personalized to you.

Complete Guide to BMR & TDEE

Your Basal Metabolic Rate (BMR) represents the minimum number of calories your body needs to perform essential life functions like breathing, circulation, and cell production. Understanding your BMR is the foundation of any effective nutrition plan.

The Mifflin-St Jeor equation is the gold standard for BMR calculation. Combined with your activity level, it gives you your Total Daily Energy Expenditure (TDEE) — the total calories you burn each day.

How to Use Your Results

  • Weight Loss: Eat 300-500 calories below your TDEE for safe, sustainable fat loss
  • Maintenance: Eat at your TDEE to maintain your current weight
  • Weight Gain: Eat 300-500 calories above your TDEE for lean muscle building
  • Never eat below your BMR — your body needs these calories for basic functions
  • Use kCal AI to accurately track your daily calorie intake with a simple photo

Frequently Asked Questions

Everything you need to know about BMR and calorie tracking

Track Your Calories with AI Precision

Download kCal AI for free and start tracking your meals instantly. Available on iOS and Android.