How Many Calories Do You Need Per Day?
Your daily calorie needs depend on your age, gender, height, weight and activity level. Our calorie calculator uses the Mifflin-St Jeor equation — the most accurate formula recommended by the American Council on Exercise and widely used by registered dietitians worldwide.
The calculation works in two steps. First we calculate your Basal Metabolic Rate (BMR) — the calories your body needs just to function at rest. Then we multiply by your activity factor to get your Total Daily Energy Expenditure (TDEE) — the total calories you burn in a day.
The Mifflin-St Jeor Formula
- Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
- Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
- TDEE = BMR × Activity Factor
Activity Level Multipliers
- Sedentary (desk job, no exercise) — BMR × 1.2
- Lightly active (exercise 1-3 days/week) — BMR × 1.375
- Moderately active (exercise 3-5 days/week) — BMR × 1.55
- Very active (exercise 6-7 days/week) — BMR × 1.725
- Extra active (athlete or physical job) — BMR × 1.9
How to Create a Calorie Deficit for Weight Loss
To lose weight, you need to consume fewer calories than you burn — creating a calorie deficit. A deficit of 500 calories per day results in approximately 1 pound of weight loss per week. A 1,000 calorie deficit results in approximately 2 pounds per week. Going below 1,200 calories per day for women or 1,500 for men is generally not recommended without medical supervision.
⚠️ Medical Disclaimer: This calorie calculator provides estimates for general informational purposes only. Individual calorie needs vary based on many factors. Always consult a registered dietitian or healthcare provider before making significant changes to your diet, especially if you have any medical conditions.
Frequently Asked Questions
How many calories should I eat to lose weight? +
To lose weight you need to consume fewer calories than you burn. A deficit of 500 calories per day below your TDEE results in approximately 1 pound of weight loss per week. A 250 calorie deficit leads to about 0.5 pounds per week. Use the goal selector above to see your specific calorie target for weight loss.
What is BMR and TDEE? +
BMR (Basal Metabolic Rate) is the number of calories your body needs to maintain basic functions at complete rest — breathing, circulation and cell production. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by your activity level — the total calories you burn in a full day including all physical activity.
How accurate is this calorie calculator? +
Our calculator uses the Mifflin-St Jeor equation which is considered the most accurate formula for estimating BMR for most people — within 10% accuracy for the majority of adults. Factors like muscle mass, medical conditions and genetics can affect actual calorie needs. Use the result as a starting point and adjust based on your real-world results.
How many calories do I need to build muscle? +
To build muscle you need a caloric surplus — eating more than you burn. A surplus of 250-500 calories per day is generally recommended for lean muscle gain. Eating too many excess calories leads to fat gain alongside muscle. Combine the caloric surplus with adequate protein intake (0.7-1g per pound of body weight) and progressive resistance training.
What is the minimum number of calories I should eat? +
Most health guidelines recommend a minimum of 1,200 calories per day for women and 1,500 calories per day for men to ensure adequate nutrition. Going below these levels can lead to nutrient deficiencies, muscle loss and metabolic slowdown. Very low calorie diets should only be followed under medical supervision.