Calorie Calculator
Find out how many calories you need each day to lose, maintain, or gain weight. Enter your details below and get your estimated daily calories in seconds, free, no sign-up.
How the calorie calculator works
This calculator estimates the calories your body burns in a day, then shows targets for losing or maintaining weight. It works in two steps, using equations validated in nutrition research.
Step 1: Your BMR (calories at rest)
Your basal metabolic rate (BMR) is the energy your body uses just to keep you alive, breathing, circulating blood, and repairing cells, if you did nothing all day. The calculator estimates it with the Mifflin-St Jeor equation, the most widely validated formula for resting energy.
Step 2: Your TDEE (resting calories plus activity)
Your total daily energy expenditure (TDEE) is your BMR multiplied by an activity factor that reflects how much you move. This is your maintenance level, eat that many calories and your weight stays about the same.
Your weight-loss target
To lose weight you eat a little less than your TDEE, a calorie deficit. The calculator suggests a gentle deficit (about 250 calories below maintenance) and a moderate one (about 500 below), which usually lead to a steady, sustainable loss of around 0.25 to 0.5 kg (0.5 to 1 lb) per week.
Frequently asked questions
How many calories should I eat a day?
Most people maintain their weight at their TDEE, which for many adults falls somewhere between roughly 1,800 and 2,500 calories a day, though it varies with age, sex, size, and activity. To lose weight, aim for about 250 to 500 calories below your maintenance level. Enter your details above for a personalised estimate.
Is this calorie calculator accurate?
It uses the Mifflin-St Jeor equation, which research shows predicts resting energy more accurately than older formulas for most people. Still, it is an estimate, not a lab measurement, and real needs vary by individual. Treat the number as a smart starting point and adjust based on how your weight actually changes over a few weeks.
What is the difference between BMR and TDEE?
Your BMR is the calories you burn at complete rest. Your TDEE is your BMR plus the calories you burn through daily activity and exercise. TDEE is the number that matters for weight management, because it reflects everything you burn in a real day.
How big a calorie deficit is safe?
A deficit of about 250 to 500 calories a day is practical and sustainable for most people, leading to roughly 0.25 to 0.5 kg (0.5 to 1 lb) of loss per week. Very aggressive deficits are hard to maintain and can cost you muscle, so most guidelines suggest not eating below about 1,200 calories (women) or 1,500 (men) without medical supervision.
Do I need to count calories perfectly to lose weight?
No. Consistency matters far more than precision. Logging most days, even with rough portions, gives you the feedback you need to adjust. A tracking app like CalcEat makes it easy by estimating calories from a photo of your meal.