Calorie & BMR Calculator
Enter your age, sex, height, weight and activity level to estimate your basal metabolic rate (BMR) and the daily calories you need to maintain your weight (TDEE), plus targets for gentle weight loss or gain.
BMR and TDEE explained
Your basal metabolic rate is the energy your body uses at complete rest just to keep you alive — breathing, circulation, and cell repair. This calculator uses the Mifflin–St Jeor equation, the formula most dietitians regard as the most accurate for the general population.
Your Total Daily Energy Expenditure (TDEE) multiplies your BMR by an activity factor to account for movement and exercise. Eating around your TDEE keeps your weight stable.
Using the numbers for a goal
To lose weight gradually, eat a few hundred calories below your TDEE; to gain, eat above it. A deficit or surplus of about 550 calories a day corresponds to roughly half a kilogram of change per week.
These are estimates. Real energy needs vary with genetics, body composition and activity, so adjust based on what the scale actually does over a few weeks.
Frequently asked questions
How many calories do I need per day?
Enter your details above to estimate your maintenance calories (TDEE). It's your BMR multiplied by an activity factor; eat around that figure to maintain your weight.
What formula does this use?
It uses the Mifflin–St Jeor equation for BMR, which is widely considered the most accurate for most adults, then applies a standard activity multiplier for TDEE.
How big a calorie deficit should I aim for?
A modest deficit of roughly 250–550 calories a day supports steady, sustainable weight loss of about 0.25–0.5 kg per week.