About Our TDEE Calculator
Understanding the science behind calculating your Total Daily Energy Expenditure
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a 24-hour period. It's the sum of your Basal Metabolic Rate (BMR) plus additional calories burned through physical activity, digestion (thermic effect of food), and other bodily functions.
Understanding your TDEE is crucial for effective weight management:
- To maintain weight: Consume calories equal to your TDEE
- To lose weight: Consume fewer calories than your TDEE
- To gain weight: Consume more calories than your TDEE
TDEE Components
Basal Metabolic Rate (60-70%)
Calories needed for basic life functions at rest
Physical Activity (15-30%)
Calories burned through exercise and daily movement
Thermic Effect of Food (10%)
Calories used to digest, absorb, and process nutrients
Non-Exercise Activity Thermogenesis (NEAT)
Calories burned through fidgeting, maintaining posture, etc.
How We Calculate Your TDEE
Our calculator first determines your Basal Metabolic Rate (BMR) using scientifically validated formulas, then applies an activity multiplier based on your lifestyle to estimate your total daily calorie needs.
Mifflin-St Jeor Equation
This is our primary formula and is considered the most accurate for most people. Published in 1990, it's been validated by research as more accurate than previous formulas.
For men:
BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) + 5
For women:
BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) - 161
After calculating your BMR, we multiply it by an activity factor to determine your TDEE:
- Sedentary (little/no exercise): BMR × 1.2
- Lightly active (1-3 days/week): BMR × 1.375
- Moderately active (3-5 days/week): BMR × 1.55
- Very active (6-7 days/week): BMR × 1.725
- Extremely active (athletes): BMR × 1.9
Why We Use This Formula
- Most accurate for the general population
- Validated by multiple research studies
- Accounts for age, gender, height, and weight
- More accurate than older formulas like Harris-Benedict
Example Calculation
For a 30-year-old man who is 180cm tall, weighs 80kg, and is moderately active:
BMR = (10 × 80) + (6.25 × 180) - (5 × 30) + 5
BMR = 800 + 1125 - 150 + 5 = 1,780 calories
TDEE = 1,780 × 1.55 = 2,759 calories per day
Your activity level has a significant impact on your TDEE. Selecting the appropriate activity level is crucial for an accurate calculation. Here's a detailed breakdown of each level:
Sedentary
Little or no exercise, desk job
• Multiplier: BMR × 1.2
• Example: Office worker who does little physical activity
Lightly Active
Light exercise 1-3 days/week
• Multiplier: BMR × 1.375
• Example: Office worker who walks to work and exercises 1-3 times per week
Moderately Active
Moderate exercise 3-5 days/week
• Multiplier: BMR × 1.55
• Example: Person who exercises 3-5 days per week for 30-60 minutes
Very Active
Hard exercise 6-7 days/week
• Multiplier: BMR × 1.725
• Example: Person who exercises hard almost every day or has a physically demanding job
Extremely Active
Very hard exercise, physical job or training twice daily
• Multiplier: BMR × 1.9
• Example: Professional athlete or person with very physically demanding job
Choosing the Right Activity Level
Most people tend to overestimate their activity level. If you're unsure, it's generally better to select a lower activity level and adjust based on your results over time. Remember that brief periods of intense exercise don't necessarily make you "very active" if you're sedentary the rest of the day.
While our calculator uses the most scientifically validated formulas available, it's important to understand that all TDEE calculations are estimates. Several factors can affect the accuracy:
Factors Affecting Accuracy
- Individual Metabolism Variations
Metabolic rates can vary by up to 20% between individuals of the same age, weight, height, and gender.
- Body Composition
Two people with the same weight can have different calorie needs if one has more muscle mass.
- Hormonal Factors
Thyroid issues, insulin resistance, and other hormonal conditions can affect metabolism.
- Age-Related Changes
Metabolism naturally slows with age, sometimes beyond what formulas predict.
How to Improve Accuracy
- Track Your Results
Monitor your weight over 2-3 weeks while eating at your calculated TDEE and adjust as needed.
- Use Body Fat Measurements
If possible, use the Katch-McArdle formula with an accurate body fat percentage measurement.
- Be Honest About Activity
Most people overestimate their activity level. When in doubt, choose a lower activity multiplier.
- Consider Professional Testing
For the most accurate results, consider metabolic testing at a sports performance center.
Remember: TDEE Is a Starting Point
Your calculated TDEE should be viewed as a starting point, not an absolute value. The true test is how your body responds to a given calorie intake over time. Be prepared to make adjustments based on your results and goals.
Once you've calculated your TDEE, you can use this information to create an effective nutrition plan based on your goals:
Weight Maintenance
Consume calories equal to your TDEE. This will maintain your current weight while providing enough energy for your daily activities.
Example:
TDEE = 2,500 calories
Daily intake = 2,500 calories
Weight Loss
Create a moderate calorie deficit by consuming less than your TDEE. A deficit of 500 calories per day can lead to approximately 1 pound of weight loss per week.
Example:
TDEE = 2,500 calories
Daily intake = 2,000 calories
Weekly deficit = 3,500 calories
Weight Gain/Muscle Building
Create a calorie surplus by consuming more than your TDEE. A surplus of 250-500 calories per day supports muscle growth while minimizing fat gain.
Example:
TDEE = 2,500 calories
Daily intake = 2,750-3,000 calories
Weekly surplus = 1,750-3,500 calories
Macronutrient Distribution
Beyond total calories, distributing your intake among macronutrients (protein, carbohydrates, and fats) is important for optimal health and performance. Our calculator provides recommended macronutrient distributions based on your goals:
| Goal | Protein | Carbohydrates | Fats |
|---|---|---|---|
| General Health | 30% (1.6-2.2g/kg) | 45-50% | 25-30% |
| Weight Loss | 35-40% (2.0-2.4g/kg) | 30-35% | 25-30% |
| Muscle Building | 30-35% (1.8-2.2g/kg) | 45-55% | 15-25% |
Final Tips for Success
Be consistent: Track your intake accurately and consistently for best results.
Be patient: Sustainable body composition changes take time.
Adjust as needed: If you're not seeing results after 2-3 weeks, adjust your calorie intake.
Focus on nutrition quality: Calories matter, but so does the nutritional value of your food.
Recalculate periodically: As your weight and activity levels change, so will your TDEE.