Calorie Calculator: Your Daily Calorie Needs
Enter your sex, age, height, weight and activity level: your BMR, your total daily energy expenditure and targets to maintain, lose or gain weight appear instantly. Nothing is sent anywhere.
- Mifflin-St Jeor formula
- 5 activity levels
- Macro breakdown
- Free
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How to calculate your daily calories?
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Fill in your profile
Sex, age, height and weight, in lb and ft/in or in kg and cm: these are the inputs of the Mifflin-St Jeor formula.
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Choose your activity level
Pick the one of 5 levels that matches your typical week, from sedentary to extremely active.
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Read your targets
BMR, daily energy expenditure, calories to maintain, lose or gain weight, and a suggested macronutrient split.
Your calorie needs, calculated and explained
Basal metabolic rate (BMR)
The energy your body burns at rest, calculated with the Mifflin-St Jeor equation, one of the most widely used today.
Total daily energy expenditure (TDEE)
Your BMR multiplied by your activity factor, from 1.2 for a sedentary lifestyle to 1.9 for very intense activity.
Maintain, lose or gain
Calories to keep your weight steady, lose at a moderate pace (−500 Calories a day, never below a safe floor) or build muscle (+300 Calories a day).
Suggested macros
A split of your calories between protein, carbs and fat, to give you a ballpark figure.
How to calculate your BMR
Your basal metabolic rate is the energy you burn at complete rest to keep your heart beating, breathe, run your brain and hold your body temperature. On food labels, a Calorie with a capital C is a kilocalorie: 1 Cal = 1 kcal. The Mifflin-St Jeor equation estimates BMR as 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years), then + 5 for men or − 161 for women; the tool converts pounds and feet for you. For a 35-year-old woman who is 5 ft 5 in (165.1 cm) and 132 lb (59.9 kg): 598.7 + 1,031.9 − 175 − 161 ≈ 1,295 Calories a day. For a 30-year-old man who is 5 ft 11 in (180.3 cm) and 165 lb (74.8 kg): 748.4 + 1,127.1 − 150 + 5 ≈ 1,731 Calories. That's the bare minimum: you always burn more as soon as you move.
From BMR to total daily energy expenditure
Your total daily energy expenditure (TDEE) is your BMR multiplied by an activity factor: 1.2 for a sedentary lifestyle, 1.375 for light activity, 1.55 for moderate activity, 1.725 for very active people and 1.9 for extremely active people, such as a physical job combined with daily training. Our 35-year-old woman, moderately active, burns about 1,295 × 1.55 ≈ 2,007 Calories a day; if she were sedentary, it would be about 1,554. The man in the example, moderately active, burns about 2,682 Calories. The most common mistake is to overestimate your activity level: when in doubt, pick the lower one.
Losing or gaining weight: sensible targets
To lose weight at a reasonable pace, the usual approach is to eat 500 Calories a day less than your TDEE, or about 3,500 Calories a week. Since a pound of body fat stores roughly 3,500 Calories (about 7,700 kcal per kilogram), that works out in theory to about 1 lb (0.45 kg) a week; in practice, the pace varies from person to person. The calculator won't suggest going below a safe floor, because an overly strict diet is tiring and makes regaining weight more likely. To build muscle, add about 300 Calories a day. These figures are estimates for adults: they don't apply during pregnancy or breastfeeding, or if you have a medical condition. For personal advice, talk to a doctor or a registered dietitian.
Frequently Asked Questions
How many calories should a woman eat per day?
It depends on age, height, weight and activity. A 35-year-old woman who is 5 ft 5 in and 132 lb burns about 1,550 Calories a day if she's sedentary, and about 2,000 if she's moderately active.
How many calories should I eat to lose weight?
A common guideline is to eat 500 Calories a day less than your daily energy expenditure, without going too low. With a TDEE of 2,000 Calories, that means about 1,500 Calories a day.
What's the difference between BMR and TDEE?
BMR is what you burn at complete rest. TDEE adds your movement and physical activity on top: it's the number to use as a baseline to maintain, lose or gain weight.
What is the Mifflin-St Jeor equation?
BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years), + 5 for men or − 161 for women. Published in 1990, it's one of the reference formulas for adults.
How accurate is the result?
It's a statistical estimate: depending on your body composition and lifestyle, your real needs can differ by 10% or more. Track your weight over a few weeks and adjust; if in doubt, ask a healthcare professional.