Free health tool
Calorie Calculator
Estimate your daily calorie needs for weight maintenance, loss, or gain based on your personal measurements and activity level.
Calculate your daily calories
How to use this calculator
- Select your gender.
- Enter your age, height in cm, and current weight in kg.
- Choose the activity level that best reflects your typical week — be honest, most people overestimate activity.
- Click Calculate Calories.
- The table shows calorie targets for different goals: maintenance, mild loss (−0.25 kg/week), loss (−0.5 kg/week), mild gain, and gain.
How daily calorie needs are calculated
Your daily calorie need is estimated by multiplying your Basal Metabolic Rate (BMR) by an activity factor. BMR is calculated using the Mifflin-St Jeor equation, widely considered the most accurate for most adults.
Example (female, 28 years, 165 cm, 65 kg, lightly active)
BMR = 10×65 + 6.25×165 − 5×28 − 161 = 650 + 1031.25 − 140 − 161 = 1,380 kcal
TDEE = 1,380 × 1.375 (lightly active) = 1,898 kcal/day
To lose approximately 0.5 kg per week, a deficit of ~500 kcal/day is commonly used: 1,898 − 500 = 1,398 kcal/day target.
Limitations
- Calorie estimates can vary ±20% from actual individual needs due to metabolic variation.
- Activity multipliers are broad categories — actual calorie burn varies with exercise intensity, body composition, and fitness level.
- The formula does not account for metabolic adaptation — the body adjusts energy use in response to sustained calorie restriction.
- Certain medical conditions (thyroid disorders, PCOS, diabetes) and medications significantly affect calorie metabolism.
- This calculator should not be used to set calorie targets below 1,200 kcal/day (women) or 1,500 kcal/day (men) without medical supervision.
Frequently asked questions
How many calories do I need to lose weight?+−
A common guideline is a deficit of 500 kcal per day below your TDEE, which is associated with approximately 0.5 kg of fat loss per week. A smaller deficit of 250 kcal/day may be more sustainable and easier to maintain over time. Avoid eating below your BMR without medical supervision.
Why do my actual results differ from the calculator?+−
Calorie formulas are population estimates and can vary ±20% or more from an individual's true energy needs. Factors like gut microbiome, metabolic adaptation, sleep quality, stress hormones, and medication all affect how many calories your body actually uses.
What happens if I eat too few calories?+−
Very low calorie intake for extended periods can reduce muscle mass, slow your metabolism, cause nutrient deficiencies, affect hormonal balance, and reduce bone density. Weight loss is rarely linear and sustainable change usually involves gradual, modest adjustments.
Is it possible to eat too many calories on a 'healthy' diet?+−
Yes. Calorie balance matters regardless of food quality. Nutritious foods can still contribute to weight gain if consumed in excess of your energy needs. Food quality and calorie intake both matter for long-term health.
How does activity level affect my calorie needs?+−
Physical activity can significantly increase calorie needs. The difference between a sedentary and very active lifestyle can be 600–1,000 kcal or more per day for the same person. Choosing the right activity multiplier is important for an accurate TDEE estimate.
Should I eat the same calories every day?+−
Not necessarily. Some people find it more practical to aim for a weekly average rather than a strict daily target. On days with high activity, eating more is reasonable. Consistency over time matters more than perfection on any single day.
References
Health disclaimer
This calculator is for general informational purposes only and does not replace professional medical advice. Always consult a qualified healthcare provider before making significant changes to your diet or calorie intake.