The Calorie Calculator estimates how many calories your body needs each day. Enter your age, gender, height, weight, and activity level and it calculates your BMR (the calories you burn at complete rest) and your TDEE (Total Daily Energy Expenditure — the calories you burn in a typical day including activity).
It then shows daily calorie targets for different goals: losing weight, maintaining your weight, or gaining weight. The estimates use the Mifflin–St Jeor equation, widely regarded as the most accurate of the common formulas. Everything is calculated in your browser and nothing is stored.
How to calculate your daily calories
- Choose your units (metric or imperial) and your gender.
- Enter your age, height, and weight.
- Select the activity level that best matches your typical week.
- Read your maintenance calories (TDEE), your BMR, and the targets for weight loss or gain.
BMR vs TDEE — what is the difference?
BMR (Basal Metabolic Rate) is the number of calories your body uses just to keep you alive at rest — breathing, circulation, and basic cell function. It is the minimum energy you need if you did nothing all day.
TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor. It reflects how many calories you actually burn in a normal day once you add movement and exercise, so it is the number to focus on when planning your diet.
How to use the goal targets
- To lose weight, eat below your maintenance (TDEE) — a 500 kcal daily deficit is about 0.5 kg per week.
- To maintain weight, eat around your TDEE.
- To gain weight or build muscle, eat above your TDEE — a 250–500 kcal surplus supports steady gain.
- One kilogram of body fat is roughly 7,700 calories, which is why a 500 kcal daily change adds up to about 0.5 kg per week.
Activity levels explained
- Sedentary — desk job, little or no exercise.
- Lightly active — light exercise 1–3 days a week.
- Moderately active — moderate exercise 3–5 days a week.
- Very active — hard exercise 6–7 days a week.
- Extra active — very hard exercise, training twice a day, or a physical job.
Frequently Asked Questions
How many calories should I eat a day?
It depends on your age, gender, size, and activity. This calculator estimates your maintenance calories (TDEE) and gives targets for losing or gaining weight. Eat around your TDEE to maintain, below it to lose weight, and above it to gain.
Which formula does this calculator use?
It uses the Mifflin–St Jeor equation to estimate BMR, which studies have found to be the most accurate of the widely used formulas for most people.
What is a safe calorie deficit for weight loss?
A deficit of 250–500 calories per day is generally considered safe and sustainable, giving roughly 0.25–0.5 kg of weight loss per week. Avoid going below about 1,200 kcal (women) or 1,500 kcal (men) without medical supervision.
Are these calorie numbers exact?
No. They are well-researched estimates. Real calorie needs vary with metabolism, muscle mass, genetics, and health conditions. Use the numbers as a starting point and adjust based on your real-world results.
What is the difference between BMR and TDEE?
BMR is the calories you burn at complete rest. TDEE is your BMR plus the calories burned through daily activity and exercise, so TDEE is always higher and is the figure to use for diet planning.