🔥 Calorie Calculator — Daily Calorie Needs & BMR
Calculate your BMR and TDEE for weight loss, maintenance or gain — private, no login
What Is BMR and TDEE?
Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest just to stay alive — powering your heart, lungs, brain and cells. BMR typically accounts for 60–75% of total daily energy expenditure.
Total Daily Energy Expenditure (TDEE) is your BMR multiplied by an activity factor. It estimates the number of calories you burn in a typical day. Eating below TDEE causes weight loss; eating above causes weight gain.
TDEE = BMR × activity factor
The Mifflin-St Jeor Equation
Our calculator uses the Mifflin-St Jeor equation, published in 1990 and validated by the American Dietetic Association as the most accurate predictive formula for healthy adults:
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
For a 30-year-old woman, 165 cm, 60 kg: BMR = 10×60 + 6.25×165 − 5×30 − 161 = 1,325 kcal/day.
The result is then multiplied by your activity factor to get TDEE.
Activity Levels Explained
| Level | Factor | Description |
|---|
| Sedentary | 1.2 | Desk job, little or no exercise |
| Lightly active | 1.375 | Light exercise 1–3 days/week |
| Moderately active | 1.55 | Moderate exercise 3–5 days/week |
| Very active | 1.725 | Hard exercise 6–7 days/week |
| Extremely active | 1.9 | Hard daily exercise or physical job |
How Many Calories to Lose Weight?
Weight loss comes down to a calorie deficit. Roughly 7,700 kcal = 1 kg of body fat.
- Moderate loss (0.5 kg/week) — eat 500 kcal below TDEE
- Aggressive loss (0.7–1 kg/week) — eat 700–1000 kcal below TDEE
- Minimum safe intake — 1,200 kcal/day for women (do not go lower without medical supervision)
Tips for sustainable weight loss
- Prioritize protein (1.2–1.6 g/kg) to preserve muscle and boost satiety
- Eat fiber-rich vegetables and whole grains
- Combine cardio + resistance training — without strength training, up to 25% of weight lost is muscle
- Aim for 0.5–1 kg per week; faster loss usually rebounds
- Track with a food diary or app for at least the first 2 weeks
Frequently Asked Questions
What is BMR?
Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest to maintain vital functions like breathing, circulation and cell production. It accounts for 60-75% of your total daily energy expenditure.
Which formula does this calculator use?
We use the Mifflin-St Jeor equation for women: BMR = 10 x weight(kg) + 6.25 x height(cm) - 5 x age - 161. This is considered the most accurate predictive formula for healthy adults.
How many calories should I eat to lose weight?
For moderate weight loss (~0.5 kg/week), eat 500 calories below your TDEE. For aggressive loss, 700-1000 below. Never eat below 1200 kcal/day for women without medical supervision.
Does the calculator work for pregnant or breastfeeding women?
No. Pregnant and breastfeeding women have different calorie needs and should consult their obstetrician or a registered dietitian for personalized guidance.
Are calorie calculators accurate?
Calorie calculators give estimates (±10-15% error). Actual needs vary based on body composition, genetics, hormones, sleep, stress and medical conditions. Use the number as a starting point and adjust based on real-world results over 2-4 weeks.
Medical Disclaimer
This calorie calculator is for general reference only and does not constitute medical or nutritional advice. Calorie needs vary based on individual factors including medical conditions, medications, pregnancy and breastfeeding. Always consult a licensed healthcare provider or registered dietitian before starting a weight loss or weight gain program. See our full disclaimer.
References