WHAT IS TDEE?
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a 24-hour period. It accounts for everything from breathing and digestion to walking and intense exercise. Understanding your TDEE is the foundation of any successful nutrition plan, whether your goal is weight loss, muscle gain, or maintenance.
The Components of TDEE
Your TDEE is made up of several components:
BMR (60-70% of TDEE)
Basal Metabolic Rate - calories burned at complete rest just to keep you alive (breathing, circulation, cell production).
TEF (10% of TDEE)
Thermic Effect of Food - calories burned digesting and processing the food you eat.
NEAT (15-20% of TDEE)
Non-Exercise Activity Thermogenesis - calories burned through daily movement like walking, fidgeting, and standing.
EAT (5-10% of TDEE)
Exercise Activity Thermogenesis - calories burned through planned exercise and workouts.
The Mifflin-St Jeor Equation
Our calculator uses the Mifflin-St Jeor equation, which research has shown to be the most accurate formula for estimating BMR in most people. Developed in 1990, it's more accurate than the older Harris-Benedict equation because it better reflects modern lifestyles and body compositions.
For Men:
BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5
For Women:
BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) - 161
Once we have your BMR, we multiply it by an activity factor to get your TDEE:
| Activity Level | Multiplier | Description |
|---|---|---|
| Sedentary | ×1.2 | Desk job, minimal 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 |
| Extra Active | ×1.9 | Very hard exercise, physical job |
How to Use Your TDEE
Once you know your TDEE, you can adjust your calorie intake based on your goals:
For Weight Loss
Eat 300-500 calories below your TDEE. This creates a sustainable deficit that promotes fat loss while preserving muscle mass. A 500-calorie deficit typically results in about 0.5kg (1lb) of weight loss per week.
For Muscle Gain (Lean Bulk)
Eat 200-300 calories above your TDEE. This surplus provides energy for muscle growth while minimizing fat gain. Combined with proper strength training, expect to gain about 0.25-0.5kg per week.
For Maintenance
Eat at your TDEE to maintain your current weight. This is useful for body recomposition (building muscle while losing fat) when combined with adequate protein and strength training.
Why TDEE Calculators Are Just a Starting Point
While our TDEE calculator uses the most accurate formula available, it's important to understand that any calculator only provides an estimate. Individual metabolism can vary by up to 15% from calculated values. Factors like genetics, hormones, sleep quality, stress levels, and gut health all influence your actual energy expenditure.
The best approach is to use your calculated TDEE as a starting point, then adjust based on real-world results. If you're not losing weight at your calculated deficit, try reducing by another 100-200 calories. If you're losing too fast (more than 1kg per week), increase calories slightly.
Common TDEE Mistakes to Avoid
Overestimating Activity Level
Most people overestimate how active they are. If in doubt, choose a lower activity level and adjust up if needed.
Not Tracking Accurately
Your TDEE is only useful if you're accurately tracking your food intake. Use a food scale and track everything including cooking oils and beverages.
Eating Back Exercise Calories
Your TDEE already accounts for exercise. Don't add extra calories on workout days unless you're doing significantly more than usual.
Ignoring Metabolic Adaptation
As you lose weight, your TDEE decreases. Recalculate every 4-6 weeks or when progress stalls.
TDEE vs BMR: What's the Difference?
BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest - just to keep your basic bodily functions running. Think of it as what you'd burn if you stayed in bed all day.
TDEE (Total Daily Energy Expenditure) includes your BMR plus all additional calories burned through movement and activity. For most people, TDEE is 30-60% higher than BMR, depending on activity level.
You should never eat below your BMR for extended periods, as this can cause metabolic adaptation, muscle loss, and nutritional deficiencies. Always base your calorie targets on TDEE, not BMR.
Frequently Asked Questions
How accurate is a TDEE calculator?▼
TDEE calculators using the Mifflin-St Jeor equation are typically accurate within 10-15% for most people. For more precise measurements, you'd need laboratory testing like indirect calorimetry. However, for practical purposes, a calculator provides a good starting point that you can adjust based on results.
How often should I recalculate my TDEE?▼
Recalculate your TDEE every 4-6 weeks, or whenever you lose or gain more than 5kg. As your body composition changes, so does your metabolism. Also recalculate if your activity level changes significantly.
Why am I not losing weight at my calculated deficit?▼
Several factors could be at play: you may be underestimating food intake (very common), overestimating activity level, or experiencing water retention that masks fat loss. Give it 2-3 weeks of consistent tracking before adjusting. If still no progress, reduce calories by 100-200.
Should I eat more on workout days?▼
Your TDEE already factors in your average exercise. For most people, eating the same calories daily is simpler and just as effective. However, if you do significantly more activity than usual (like a long hike), adding 200-300 calories can help recovery.
What's the minimum calories I should eat?▼
General guidelines suggest women shouldn't go below 1200 calories and men below 1500 calories without medical supervision. Never eat below your BMR for extended periods. Aggressive deficits can cause muscle loss, nutritional deficiencies, and metabolic adaptation.