Home › Calculators › Calculators
Calorie Calculator
How many calories you need depends on your body and how active you are, not on a single round number. This calculator uses the widely used Mifflin-St Jeor equation to estimate your basal metabolic rate and your total daily energy expenditure, then shows sensible targets for maintaining, losing or gaining weight.
Use the tool
How to use the Calorie Calculator
- Enter your sex, age, weight in kilograms, height in centimetres and activity level.
- Adjust any optional settings to match your page, business or campaign.
- Click the button to generate your result instantly — nothing is uploaded; the tool runs in your browser.
- Copy the result, or download it as a file where that option appears, and paste it into your site, document or campaign.
Frequently asked questions
What is the Mifflin-St Jeor equation?
It estimates basal metabolic rate from sex, weight, height and age, and is the equation most dietitians and health bodies use as a starting point. It is an estimate, not a medical measurement.
What does the activity level change?
Your basal rate is what you burn at rest. Multiplying it by an activity factor gives total daily expenditure — the calories that maintain your current weight at your current activity.
Is a 500-calorie deficit safe for everyone?
No. The targets shown are general guides. Anyone with a medical condition, who is pregnant, or who is under 18 should get personal advice rather than following a calculator alone.