About the Calorie Calculator
Estimate your basal metabolic rate (BMR) and total daily energy expenditure (TDEE) with the Mifflin-St Jeor equation, plus calorie targets to lose, maintain or gain weight.
Key features
- BMR with the Mifflin-St Jeor equation
- Maintenance calories (TDEE) for five activity levels
- Targets to lose or gain 0.25–0.5 kg (0.5–1 lb) per week
- Metric or imperial input
- Warns about very low intakes
- Private: nothing leaves your browser
How many calories do you need?
Your daily calorie needs depend on your size, age, sex and activity level. This calculator estimates your basal metabolic rate (BMR) and your maintenance calories (TDEE), then suggests targets for gradual weight loss or gain.
The Mifflin-St Jeor equation
Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
TDEE = BMR × activity factor
Activity factors
| Level | Description | Factor |
|---|---|---|
| Sedentary | Little or no exercise | 1.2 |
| Light | Exercise 1–3 days/week | 1.375 |
| Moderate | Exercise 3–5 days/week | 1.55 |
| Active | Exercise 6–7 days/week | 1.725 |
| Very active | Hard exercise or a physical job | 1.9 |
Examples
| Person | BMR | Activity | TDEE |
|---|---|---|---|
| Man, 30, 180 cm, 80 kg | 1,780 | Moderate | ≈ 2,760 |
| Woman, 30, 165 cm, 65 kg | 1,370 | Light | ≈ 1,885 |
Tips for sustainable change
- Prioritize protein and fiber to stay full on fewer calories.
- Strength train to preserve muscle while losing fat.
- Aim for 0.25–1% of body weight per week; faster loss is harder to maintain.
- Don't go too low: intakes below about 1,200 kcal (women) or 1,500 kcal (men) are generally not recommended without medical supervision.
Estimates only, not medical or dietary advice. Consult a doctor or registered dietitian before major diet changes, especially if you are pregnant, have a medical condition or take medication.
Related calculators
Check your BMI, convert kcal to kJ with the Energy Converter, or estimate hydration with the Water Intake Calculator.
How to use the Calorie Calculator
- Enter your numbers in the fields above. Units and options can be changed at any time.
- The result updates instantly as you type; there's no calculate button to press.
- Check the breakdown under the main result for the details behind the number.
- Adjust the inputs to compare scenarios, for example a different rate or term.