BMR Calculator
Calculate your Basal Metabolic Rate — the calories you burn at complete rest.
- Per hour
- —
- Per week
- —
- Formula
- Mifflin-St Jeor
What is BMR?
Your Basal Metabolic Rate (BMR) is the number of calories your body uses at complete rest to keep essential functions running — breathing, circulation and cell repair. It is the foundation of your daily energy needs before any activity is added.
The Mifflin-St Jeor equation
This tool uses the Mifflin-St Jeor equation:
10 × weight(kg) + 6.25 × height(cm) − 5 × age + s, where s is +5 for men
and −161 for women. It is considered one of the most reliable BMR estimates for the general public.
Note: BMR is an estimate for general information and is not medical advice. Consult a qualified professional for guidance tailored to you.
How to use the BMR Calculator
- Enter your age. Type your age in years.
- Select your sex. The equation adds +5 for men and −161 for women.
- Add weight and height. Enter your weight in kilograms and height in centimetres.
- Read your BMR. See your resting calories per day, hour and week.
Frequently asked questions
Is BMR the same as daily calorie need?
No. BMR is calories burned at rest. Your total daily need (TDEE) is BMR multiplied by an activity factor — use the calorie calculator for that.
Why Mifflin-St Jeor over Harris-Benedict?
Studies have found Mifflin-St Jeor to be more accurate for modern populations, which is why it is the default here.
Can I lose weight by eating below BMR?
Eating far below BMR is generally discouraged as it can be unsustainable and unsafe. Any deficit should be planned with professional guidance.
Is my data stored?
No. The calculation runs entirely in your browser and nothing is sent to a server.