About this tool
How many calories do you need a day? The calculator uses the Mifflin-St Jeor equation, the one most dietitians use, to estimate your basal metabolic rate (BMR) - the energy your body burns at rest - and multiplies it by your activity level to get your total daily energy expenditure (TDEE). That is the amount that keeps your weight stable. From it you get a target to lose about half a kilo a week (500 kcal less) and one to gain weight slowly (300 kcal more), never below the safe minimum. It also shows a daily water guide. Everything is calculated in your browser.
How to use it
- 1 Choose your sex and type your age, height and weight.
- 2 Pick the activity level that matches your week.
- 3 Read your daily calories to keep, lose or gain weight.
- 4 Copy the link to save your numbers or share them.
Frequently asked questions
What is the difference between BMR and TDEE?
BMR (basal metabolic rate) is what your body burns at complete rest, just to stay alive. TDEE adds everything you do in the day - walking, working, exercising - and is the number to compare with what you eat.
How accurate is it?
Mifflin-St Jeor is accurate to about 10% for most healthy adults. Use the result as a starting point and adjust after two or three weeks, watching your weight.
How many calories should I eat to lose weight?
Eating about 500 kcal a day less than your TDEE usually leads to losing around 0.5 kg a week. The calculator never suggests less than 1,200 kcal for women or 1,500 kcal for men; below that, only with medical supervision.
Does it work for teenagers or during pregnancy?
No. The equation is for adults. Teenagers, pregnant or breastfeeding women and people with health conditions need a doctor or nutritionist.
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