What is TDEE?
Total daily energy expenditure, or TDEE, estimates all the energy you use during a typical day. It includes resting energy, normal movement, structured exercise, and the energy used to digest food.
The number is commonly used as a starting estimate for weight maintenance. Actual expenditure changes from day to day and can differ from an equation-based result.
How does the TDEE calculator work?
First, the calculator estimates basal metabolic rate (BMR) with Mifflin-St Jeor or revised Harris-Benedict. It then multiplies that value by the selected activity factor.
The result panel also shows weekly expenditure, a ±5% maintenance range, and values 10% below and above the estimate. These comparisons help demonstrate uncertainty; they are not automatic diet recommendations.
Activity levels used
| Level | Factor | General description |
|---|---|---|
| Sedentary | 1.20 | Little structured exercise |
| Lightly active | 1.375 | Exercise about 1–3 days per week |
| Moderately active | 1.55 | Exercise about 3–5 days per week |
| Very active | 1.725 | Hard exercise about 6–7 days per week |
| Extra active | 1.90 | Very hard training or a physically demanding occupation |
These categories are simplified. A person who exercises regularly but sits for most of the day may not fit neatly into one label. Choose a reasonable starting point and compare it with real trends.
How to use the TDEE calculator
- Choose U.S. or metric units.
- Enter age and select the sex coefficient required by the equation.
- Select a BMR equation.
- Enter current height and weight.
- Choose the activity level that best represents a typical week.
- Select Calculate TDEE and review the estimate and range.
How accurate is a TDEE estimate?
There are two major uncertainty sources: the predicted BMR and the activity multiplier. Research equations estimate group averages, while activity categories compress complex behavior into a single factor.
A practical approach is to treat the result as a starting point and track average intake and body weight consistently for several weeks. If you want to compare gradual weight-change targets, the calorie calculator applies a transparent adjustment to maintenance; seek professional guidance when accurate energy planning is important.