Calorie Calculator - Free BMR and TDEE Calculator for Daily Calorie Needs
Basic Information
Activity & Goals
Enter your target weight to calculate time to reach your goal
Enter your information and click "Calculate Calories" to see your personalized daily calorie needs and macronutrient breakdown.
Understanding Calorie Calculation and Nutrition
🔥What is BMR (Basal Metabolic Rate)?
BMR is the number of calories your body needs to perform essential life-sustaining functions while at complete rest. This includes breathing, circulation, nutrient processing, and cell production. BMR typically accounts for 60-75% of your total daily calorie expenditure.
Factors affecting BMR include age, gender, body composition, genetics, and hormonal balance. Men generally have higher BMR than women due to greater muscle mass. BMR decreases with age as muscle mass naturally declines, making it important to adjust calorie intake as you get older. Learn more from WHO Healthy Diet Guidelines.
⚡What is TDEE (Total Daily Energy Expenditure)?
TDEE is the total number of calories you burn in a 24-hour period, combining your BMR with calories burned through physical activity and digestion (thermic effect of food). TDEE is calculated by multiplying your BMR by an activity factor that ranges from 1.2 (sedentary) to 1.9 (very active).
Understanding your TDEE is crucial for effective weight management. To lose weight, consume fewer calories than your TDEE (calorie deficit). To gain weight or build muscle, consume more calories than your TDEE (calorie surplus). To maintain your current weight, match your calorie intake to your TDEE.
📐BMR Calculation Formulas
Mifflin-St Jeor Equation (Recommended):
Men: (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5
Women: (10 × weight in kg) + (6.25 × height in cm) - (5 × age) - 161
Harris-Benedict Equation (Classic):
An older formula that tends to overestimate BMR by 5-10% for modern populations. Mifflin-St Jeor is generally more accurate for most people today.
🏃Activity Level Multipliers
- • Sedentary (1.2): Little or no exercise, desk job
- • Light (1.375): Light exercise or sports 1-3 days/week
- • Moderate (1.55): Moderate exercise 4-5 days/week
- • Active (1.725): Hard exercise 6-7 days/week
- • Very Active (1.9): Very intense exercise daily, physical job
Choose the level that best matches your current lifestyle. Be honest - most people fall into the sedentary or light category. Overestimating activity level can lead to consuming too many calories.
📉Safe Weight Loss Guidelines
Safe and sustainable weight loss typically ranges from 0.5 to 2 pounds per week. This requires a daily calorie deficit of 250-1,000 calories below your TDEE (since 1 pound of fat equals approximately 3,500 calories).
- • Never go below: 1,200 cal/day (women) or 1,500 cal/day (men)
- • Moderate deficit: 500 cal/day = 1 lb/week loss (recommended)
- • Aggressive deficit: 1,000 cal/day = 2 lb/week loss (short-term only)
- • Mild deficit: 250 cal/day = 0.5 lb/week loss (sustainable)
Very low calorie diets can lead to muscle loss, nutritional deficiencies, metabolic slowdown, and are difficult to maintain long-term.
🥗Macronutrient Breakdown
Macronutrients are the three main categories of nutrients your body needs in large amounts: protein, carbohydrates, and fats. Each provides different amounts of energy per gram.
- • Protein: 4 calories per gram - builds and repairs tissues
- • Carbohydrates: 4 calories per gram - primary energy source
- • Fats: 9 calories per gram - hormone production, nutrient absorption
Recommended split: 40% carbs, 30% protein, 30% fats. Adjust based on goals: increase protein for muscle building or weight loss, increase carbs for endurance activities.
Average Daily Calorie Needs by Demographics
| Age Group | Male (Sedentary) | Male (Active) | Female (Sedentary) | Female (Active) |
|---|---|---|---|---|
| 19-25 years | 2,400 | 3,000 | 2,000 | 2,400 |
| 26-35 years | 2,400 | 2,800 | 1,800 | 2,200 |
| 36-50 years | 2,200 | 2,600 | 1,800 | 2,200 |
| 51-65 years | 2,000 | 2,400 | 1,600 | 2,000 |
| 65+ years | 2,000 | 2,400 | 1,600 | 2,000 |
These are general guidelines from USDA Dietary Guidelines. Individual needs vary based on metabolism, body composition, and specific health conditions.
Frequently Asked Questions
How many calories should I eat per day?
Daily calorie needs depend on your age, gender, weight, height, and activity level. For most adults, this ranges from 1,600-3,000 calories per day. Men typically need 2,000-3,000 calories, while women need 1,600-2,400 calories. Use our calorie calculator to get a personalized estimate based on your BMR (Basal Metabolic Rate) and TDEE (Total Daily Energy Expenditure).
What is BMR and how is it calculated?
BMR (Basal Metabolic Rate) is the number of calories your body needs to perform basic life-sustaining functions at rest, such as breathing, circulation, and cell production. The most accurate formulas are Mifflin-St Jeor: (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5 for men (subtract 161 for women), and Harris-Benedict which uses slightly different coefficients. BMR typically accounts for 60-75% of total daily calories.
What is TDEE and why is it important?
TDEE (Total Daily Energy Expenditure) is the total number of calories you burn in a day, including BMR plus calories burned through physical activity. TDEE = BMR × activity multiplier (1.2 for sedentary, 1.375 for light exercise, 1.55 for moderate, 1.725 for active, 1.9 for very active). Knowing your TDEE is crucial for weight management: eat below TDEE to lose weight, at TDEE to maintain, or above TDEE to gain weight.
How many calories should I eat to lose weight?
For safe weight loss, create a calorie deficit of 500-1,000 calories per day below your TDEE, which results in losing 1-2 lbs per week. However, never go below 1,200 calories/day for women or 1,500 calories/day for men without medical supervision. A moderate deficit (500 cal/day = 1 lb/week loss) is more sustainable than aggressive deficits, which can lead to muscle loss and nutritional deficiencies.
How should I split my macronutrients?
A balanced macronutrient split is typically 40% carbohydrates, 30% protein, and 30% fats. For weight loss, increase protein to 35-40% to preserve muscle mass. For muscle gain, aim for 30-35% protein, 45-50% carbs, and 20-25% fats. Calculate grams by dividing calories by 4 for protein and carbs (4 cal/gram), and by 9 for fats (9 cal/gram). Adjust based on your activity level and goals.
Is the Mifflin-St Jeor or Harris-Benedict formula more accurate?
The Mifflin-St Jeor equation is generally considered more accurate for modern populations. Developed in 1990, it reflects current body compositions better than the Harris-Benedict equation from 1919. Studies show Mifflin-St Jeor has an accuracy rate of about 10% for predicting BMR in healthy individuals, while Harris-Benedict can be 5-10% less accurate. However, both provide good estimates for calorie planning.
How long will it take to reach my weight goal?
Weight loss timeline depends on your calorie deficit. A 500 calorie daily deficit (3,500 cal/week) results in losing approximately 1 lb per week. For example, losing 20 lbs would take about 20 weeks (5 months) at this rate. Safe weight loss is 0.5-2 lbs per week. Faster loss may lead to muscle loss and is harder to maintain. Use our calculator's target weight feature to estimate your timeline based on your chosen deficit.
Should I eat back calories burned from exercise?
If you've calculated your TDEE using an activity multiplier, your exercise is already accounted for in your calorie target, so you don't need to eat back exercise calories. However, if you calculated maintenance calories using sedentary multiplier and do additional exercise, you may need to eat back 50-75% of exercise calories to avoid excessive deficit. Monitor your energy levels, recovery, and weight changes to adjust as needed.