Total daily energy expenditure is everything you burn in a day: resting metabolism, every step and fidget, deliberate exercise, and the energy spent digesting food. It is your maintenance level — eat that much and your weight holds steady.
- What it measures
- Total calories burned per day
- Formula
- TDEE = BMR × activity factor
- BMR equation
- Mifflin-St Jeor (1990)
- Activity factors
- 1.2 (sedentary) to 1.9 (athlete)
- Also called
- Maintenance calories
Formula
Mifflin-St Jeor BMR with standard activity multipliersTDEE = BMR × activity factor
- BMR
- — Basal metabolic rate — calories burned at complete rest
- activity factor
- — 1.2 sedentary · 1.375 light · 1.55 moderate · 1.725 very active · 1.9 extremely active
The activity multipliers date to the original Harris-Benedict work and remain the standard approach. They are coarse by design — the gap between adjacent levels is 10–15%, which is roughly the precision the method supports.
TDEE Calculator examples
| Input | Result | Category |
|---|---|---|
| Man, 30, 5'10", 180 lb, moderate | 2,763 cal/day | Maintenance calories |
| Man, 30, 5'10", 180 lb, sedentary | 2,139 cal/day | Maintenance calories |
| Man, 25, 6'0", 200 lb, very active | 3,330 cal/day | Maintenance calories |
| Woman, 30, 5'5", 150 lb, moderate | 2,172 cal/day | Maintenance calories |
| Woman, 30, 5'5", 150 lb, sedentary | 1,682 cal/day | Maintenance calories |
| Woman, 40, 5'4", 140 lb, light | 1,774 cal/day | Maintenance calories |
What makes up your TDEE?
Four components, and they are not equally under your control.
| Component | Share of TDEE | What it is |
|---|---|---|
| Basal metabolic rate | 60–70% | Keeping you alive at rest |
| NEAT | 15–30% | Walking, standing, fidgeting, everything unplanned |
| Thermic effect of food | ~10% | Energy spent digesting and absorbing |
| Exercise | 5–15% | Deliberate training |
The surprise for most people is how small the exercise slice is and how large NEAT is. Non-exercise activity thermogenesis varies by as much as 2,000 calories a day between individuals of similar size, which is why two people with identical workouts and diets can have very different outcomes.
Choosing your activity level honestly
This is where most TDEE estimates go wrong. The multipliers describe your whole life, not your gym schedule, and people routinely pick a level or two too high.
- Sedentary (1.2) — desk job, no structured exercise. This describes more people than choose it.
- Lightly active (1.375) — desk job plus light exercise one to three days a week, or a job that keeps you on your feet.
- Moderately active (1.55) — genuine training three to five days a week, or a physically active job.
- Very active (1.725) — hard training six or seven days a week, or a demanding physical job plus exercise.
- Extremely active (1.9) — manual labour plus daily training, or two-a-day sessions. Very few people belong here.
How accurate is a TDEE estimate?
Treat the number as a starting point with a margin of roughly ±200–300 calories. It is built on a predicted BMR — itself accurate to about 10% — multiplied by a coarse activity factor, so the errors compound.
The way to find your real maintenance level is to use the estimate for two to three weeks while tracking intake and weighing yourself under consistent conditions. If weight holds steady, the estimate was right. If it drifts by more than about half a kilogram a week in either direction, adjust by 200 calories and repeat.
Using TDEE to change weight
Eat at TDEE to maintain, below it to lose, above it to gain. A pound of body fat stores roughly 3,500 calories, so a 500-calorie daily deficit predicts about a pound a week.
That prediction holds well early and drifts later. As you lose weight, TDEE falls — a smaller body costs less to run and less to move — so the same intake produces a shrinking deficit. Recalculating every 5–10 lb of change keeps the plan honest.
Why your tracker disagrees
Wearables typically overestimate calorie burn, particularly for exercise. Validation studies have found errors of 27% to over 90% for energy expenditure even in devices whose heart-rate tracking is accurate.
They also double-count: a tracker reports total burn including BMR, so adding 'exercise calories' on top of a TDEE that already includes an activity multiplier inflates the target substantially.
Frequently asked questions
How many calories should I eat to lose weight?
Subtract 300–500 calories from your TDEE for a loss of roughly half to one pound per week. Larger deficits speed things up initially but are harder to sustain and cost more lean mass along the way.
Is TDEE the same as maintenance calories?
Yes, they mean the same thing. TDEE is the amount you burn per day, so eating exactly that much maintains your current weight — hence the alternative name.
Should I eat back my exercise calories?
Not if you selected an activity level that already reflects your training. The multiplier includes exercise, so adding tracker-reported burn on top counts the same activity twice.
Why did my weight stall at the same calories?
As you lose weight your TDEE falls, because a smaller body costs less to maintain and to move. Recalculate every 5–10 pounds lost, and account for the reduced spontaneous movement that often accompanies a deficit.
How accurate are TDEE calculators?
Within about 200–300 calories for most people. The estimate depends on a predicted BMR and a coarse activity factor, so verify it against two to three weeks of tracked intake and stable weight rather than trusting it outright.
Does TDEE change day to day?
Yes, considerably. A hard training day can run several hundred calories above a rest day. Most people find it easier to eat a consistent daily amount and let it average out across the week.
Sources
- A new predictive equation for resting energy expenditure in healthy individuals — Mifflin et al., American Journal of Clinical Nutrition, 1990
- Dietary Reference Intakes for Energy — National Academies of Sciences, Engineering, and Medicine, 2023
- Non-exercise activity thermogenesis (NEAT) — Levine, Best Practice & Research Clinical Endocrinology & Metabolism, 2002
- Accuracy in wrist-worn, sensor-based measurements of heart rate and energy expenditure in a diverse cohort — Shcherbina et al., Journal of Personalized Medicine, 2017