What is TDEE?
TDEE stands for total daily energy expenditure: every calorie your body burns in a 24-hour stretch. People tend to picture exercise when they think about burning calories, but workouts are usually the smallest slice. The bulk of your TDEE is your basal metabolic rate — the energy spent running your organs, brain, and body temperature — followed by everyday movement like walking and fidgeting, then the cost of digesting food, and only then formal exercise.
That's why TDEE is the number that matters for weight change. Your weight responds to total energy in versus total energy out, not to what happened in the gym for 45 minutes.
How this TDEE calculator works
The calculator starts with your basal metabolic rate using the Mifflin-St Jeor equation, the formula with the best track record in validation studies. It also runs the older Harris-Benedict equation alongside it so you can compare, but Mifflin-St Jeor drives the headline number. Your BMR then gets multiplied by an activity factor that reflects a typical week of your life.
A quick example: a 30-year-old man, 80 kg and 180 cm, has a BMR of about 1,780 calories. If he trains three to five days a week, the moderate multiplier of 1.55 puts his TDEE near 2,760 calories. That's his maintenance level — the intake at which his weight stays put.
Want to see the resting side of the equation on its own? The BMR calculator goes deeper on that piece.
TDEE activity multipliers
Choose the level that describes your average week, not your best one. Most people overshoot by a level, and it's the most common reason a TDEE estimate misses.
| Level | Multiplier | Typical week |
|---|---|---|
| Sedentary | × 1.2 | Little or no exercise |
| Light | × 1.375 | Exercise 1–3 days a week |
| Moderate | × 1.55 | Exercise 3–5 days a week |
| Active | × 1.725 | Hard exercise 6–7 days a week |
| Very active | × 1.9 | Hard daily exercise or a physical job |
| Athlete | × 2.0 | Professional or twice-a-day training |
Using your TDEE to lose or gain weight
Once you know your TDEE, every diet decision becomes arithmetic. Eat below it and you lose; above it and you gain. A deficit of 300–500 calories a day is the sweet spot for most people — enough to produce steady loss of roughly half a pound to a pound per week, small enough that you're not fighting hunger all day. Building muscle works the same way in reverse: a modest surplus of 250–500 calories fuels growth without piling on much fat.
If you'd rather have the goal math done for you, the calorie calculator takes your TDEE and turns it straight into daily targets for cutting, maintaining, or bulking.
Why your real TDEE won't sit still
Here's the part most calculators don't mention: TDEE is a moving target. Diet for a few months and your body adapts — you weigh less, so everything costs less energy, and you unconsciously move less too. Researchers call that second effect a drop in NEAT (non-exercise activity thermogenesis), and it can quietly erase a few hundred calories of daily burn.
The practical answer is to re-run your numbers every 5–10 lbs of weight change, and to trust your scale trend over any single estimate. The calculator gets you close; your own data gets you exact.
Frequently asked questions about TDEE
What is TDEE?
TDEE (total daily energy expenditure) is the total calories you burn in a day, including BMR plus activity, exercise, and daily movement.
How is TDEE used for weight loss?
Eating fewer calories than your TDEE creates a deficit. A moderate deficit of 300–500 calories is a common starting point for sustainable fat loss.
Which activity level should I choose?
Pick the level that matches an average week, not your most active day. If you train hard 3 days per week but sit at a desk otherwise, "moderately active" is often closer than "very active."
Why might my real TDEE differ from the estimate?
Sleep, stress, hormones, muscle mass, and NEAT (fidgeting, steps) all change burn. Use the calculator as a starting point and adjust based on scale trends.
How do I use this TDEE calculator?
Enter gender, age, height, weight, and activity level, then click Calculate to see your TDEE and related calorie targets.
Sources and further reading
- Mifflin MD et al. — A new predictive equation for resting energy expenditure (Am J Clin Nutr, 1990)
- Frankenfield D et al. — Comparison of predictive equations for resting metabolic rate (J Am Diet Assoc, 2005)
- CDC — Physical activity guidelines for adults
This page is for general information only and is not medical or dietary advice. Talk to a qualified professional before making major changes to how you eat.