Understanding Total Daily Energy Expenditure (TDEE)

Your Total Daily Energy Expenditure (TDEE) is an estimation of how many calories you burn per day when exercise is taken into account. It is calculated by first figuring out your Basal Metabolic Rate (BMR), then multiplying that value by an activity multiplier.

Since your BMR represents how many calories your body burns when at rest, it is necessary to adjust the numbers upwards based on the calories you burn during the day. This is true even for those with a sedentary lifestyle. Our TDEE calculator uses the best formulas and displays your score in a way that's easy to read and meaningful.

The Formula

The most common and accurate formula used to calculate BMR today is the Mifflin-St Jeor Equation, which is what our tool utilizes:

For Men:

$BMR = 10 \times weight(kg) + 6.25 \times height(cm) - 5 \times age(y) + 5$

For Women:

$BMR = 10 \times weight(kg) + 6.25 \times height(cm) - 5 \times age(y) - 161$

Once the BMR is calculated, we apply the Physical Activity Level (PAL) multiplier:

• Sedentary: $BMR \times 1.2$
• Lightly Active: $BMR \times 1.375$
• Moderately Active: $BMR \times 1.55$
• Very Active: $BMR \times 1.725$
• Extra Active: $BMR \times 1.9$

How to Use This Calculator

1. Enter Your Stats: Provide your gender, age, weight, and height. Accurate measurements lead to accurate results.
2. Select Activity Level: Be honest about your activity. Most people overestimate their physical activity. If you work an office job and do not exercise, select "Sedentary."
3. Set Your Goal: Whether you want to maintain, lose, or gain weight, the calculator will adjust your target daily calories accordingly.
4. Review Macros: Look at the suggested protein, fat, and carbohydrate breakdown to fuel your body correctly.

WHO BMI Classification Table

| BMI Range | Category | | ----------- | ------------- | | < 18.5 | Underweight | | 18.5 – 24.9 | Normal Weight | | 25.0 – 29.9 | Overweight | | > 30.0 | Obese |

Worked Examples

Example 1: Sedentary Male

• Weight: 80kg, Height: 180cm, Age: 30
• BMR: $(10 \times 80) + (6.25 \times 180) - (5 \times 30) + 5 = 1780$ kcal
• TDEE: $1780 \times 1.2 = 2136$ kcal/day

Example 2: Moderately Active Female

• Weight: 65kg, Height: 165cm, Age: 25
• BMR: $(10 \times 65) + (6.25 \times 165) - (5 \times 25) - 161 = 1395$ kcal
• TDEE: $1395 \times 1.55 = 2162$ kcal/day

Limitations

This calculator provides an estimate based on population averages. It does not account for muscle mass vs. fat mass (body composition), hormonal health, or specific medical conditions. Athletes with high muscle mass may find their TDEE is higher than calculated, while those with very low muscle mass may find it lower. Always consult a healthcare professional before starting a new diet or exercise regimen.

FAQ

What is the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is what your body burns just to stay alive (keep organs functioning) at rest. TDEE includes BMR plus all physical activity and the thermic effect of food.

How many calories should I eat to lose weight?

A common recommendation is to subtract 500 calories from your TDEE to lose approximately 0.5kg (1lb) per week.

Should I eat my exercise calories back?

Generally, no. Since the TDEE calculation already accounts for your activity level, eating back "calories burned" tracked by watches can lead to overconsumption as those devices often overestimate burn.

How often should I recalculate my TDEE?

You should recalculate every time you lose or gain 2-5kg, as your metabolic needs change with your body weight.

Is the Mifflin-St Jeor formula accurate?

Yes, it is currently considered the most accurate formula for the general population without access to laboratory equipment like indirect calorimetry.

Does age affect TDEE?

Yes, metabolism naturally slows down with age, primarily due to the loss of lean muscle mass. This is why age is a variable in the BMR formula.