TDEE Calculator
See how many calories you burn in a day, and how that number changes with activity and weight.
TDEE calculator
Uses the National Academies' 2023 energy equations, built on doubly labeled water measurements.
What is TDEE?
TDEE — total daily energy expenditure — is all the calories you burn in a day: your resting metabolism, digesting food, and every movement. Eat about your TDEE and your weight holds steady; eat less and you lose. This calculator estimates it with the 2023 National Academies energy equations.
How this calculator works
Your TDEE comes from the 2023 National Academies energy equations, which were built on doubly labeled water measurements — the benchmark method for measuring how much energy people actually burn as they go about normal life. Rather than guessing a resting rate and scaling it up, these equations predict your whole-day burn directly from pooled doubly labeled water measurements.
You give it your sex, age, height, weight and activity level, and it returns your total daily burn. The activity level is the one judgement call, and the 2023 report describes four levels built from measured people rather than from a formula.
Every estimate carries error, and we show ours. The equations' published standard error is about ±339 calories a day for men and ±246 for women — a range that covers about two in three people. Treat the single number as a starting point and confirm it against your own weigh-ins.
For the breakdown of where those calories go, the calculator uses two further sources: your resting metabolism from the Mifflin-St Jeor equation (1990), and the share for digestion from the NIH model's roughly 10% thermic-effect assumption. Those two give an estimate of the split; the total always comes from the 2023 equation itself.
We deliberately don't use the common 1.2 to 1.9 activity multipliers other calculators apply to a resting-metabolism formula. That multiplier table is a textbook convention we couldn't trace to a primary source, so we use equations that build activity in directly.
The calculator is for adults 19 and older who are not pregnant or breastfeeding — the scope of the 2023 adult equations (the age box stops at 90). If you have a history of disordered eating, talk to a professional before counting calories.
Worked example
Take a 35-year-old man, 5 ft 10 in (178 cm), 185 lb (83.9 kg), low active. His TDEE is about 2,932 calories a day, and most men like him fall between 2,593 and 3,271.
His TDEE by activity level — the same inputs, each of the four levels:
| Activity level | TDEE |
|---|---|
| Inactive | 2,713 |
| Low active (his level) | 2,932 |
| Active | 3,120 |
| Very active | 3,482 |
Where his low-active TDEE goes — resting metabolism, digestion and activity:
| Component | Calories a day |
|---|---|
| Resting metabolism (BMR) | 1,780 |
| Digestion | 293 |
| Activity | 858 |
If he keeps the same activity level, losing weight lowers his TDEE because a lighter body burns less: after losing 10 lb it is about 2,864, after 20 lb about 2,796, and after 30 lb about 2,729.
To lose weight he eats below his TDEE. A 250-calorie deficit means eating about 2,682 a day; 500 means 2,432; 750 means 2,182; and 1,000 means 1,932 — all above the 1,500-calorie floor Harvard Health advises for men.
Typical TDEE by activity level
TDEE for some common starting points (age 40), at each of the four activity levels:
| Person | Inactive | Low active | Active | Very active |
|---|---|---|---|---|
| Woman 5 ft 4 in, 150 lb | 2,031 | 2,194 | 2,333 | 2,560 |
| Woman 5 ft 4 in, 180 lb | 2,190 | 2,359 | 2,501 | 2,731 |
| Woman 5 ft 4 in, 210 lb | 2,350 | 2,525 | 2,668 | 2,902 |
| Man 5 ft 10 in, 180 lb | 2,627 | 2,844 | 3,030 | 3,385 |
| Man 5 ft 10 in, 220 lb | 2,883 | 3,115 | 3,319 | 3,731 |
| Man 5 ft 10 in, 260 lb | 3,138 | 3,386 | 3,607 | 4,078 |
Calculated with the 2023 equations; your number depends on age, height and weight.
Why our number differs from other TDEE calculators
Most TDEE calculators take a resting-metabolism equation and multiply it by an activity factor between 1.2 and 1.9. That factor table is a textbook convention we couldn't trace to a primary source, and small changes in it move the answer a lot.
The 2023 National Academies equations instead predict total daily burn directly from doubly labeled water data — the method that tracks how much energy people actually expend. Activity is already inside the equation, chosen from four measured levels, so there's no separate multiplier to guess.
No estimate is exact, and we don't claim ours is more accurate than any particular competitor. What we do is show the published error with every result, so you can see how wide the range really is and adjust from your own weigh-ins.
In practice this means our figure can land a little above or below what a multiplier-based calculator shows for the same person. Neither is a measurement; the honest move is to pick a starting estimate, eat to it for a while, and let your own weight trend correct it.
How to choose your activity level
Inactive means everyday living only — little or no activity at work and no regular exercise (not bed rest). Low active adds some regular activity; active adds a good amount; very active means a physically demanding job, plenty of exercise, or both.
These levels come from the 2023 National Academies report, which split measured adults into quarters from least to most active. The report calls choosing your level the hardest step in the whole estimate. Pick your honest best guess, then adjust from your real weigh-ins (2023 report, chapter 7).
Using your TDEE to lose weight
To lose weight, eat below your TDEE. 500 to 1,000 calories a day below gives about 1 to 2 lb a week at first — but don't drop below 1,200 calories a day for women or 1,500 for men without a health professional's supervision (Harvard Health Publishing).
Your losses slow over time because, as the worked example shows, your weight and your TDEE both fall as you go — so the same intake becomes a smaller and smaller deficit (Hall et al., The Lancet 2011). That's why a number that worked at the start stops working months in, and why it pays to rerun the figures at your new weight.
Judge progress by weekly averages, not a single morning — day-to-day weight swings with water, salt and food still in transit. If the scale stalls, check two things: your TDEE drifts down as you lose, so rerun this at your current weight; and intake tends to creep up over time — the NIH model's authors note that real-world programs usually drift from their target (Hall et al. 2011). You can also lift the activity side of the ledger by moving more, which raises your TDEE instead of cutting your food further.
To turn your TDEE into a full day-by-day plan — a calorie target, a year-long weight projection and a timeline to your goal — use the calorie deficit calculator.
Frequently asked questions
What is the most accurate TDEE calculator?
No calculator measures you. The most reliable number comes from tracking your weight and intake over time; the 2023 report itself recommends estimating, then adjusting from your weight. This calculator uses the 2023 equations built on doubly labeled water data and shows the range that covers about two in three people.
What is my TDEE to lose weight?
Your TDEE doesn't change because you want to lose weight; you eat below it. Worked example: 2,932 minus 500 = 2,432 a day.
How much below my TDEE should I eat to lose weight?
500 to 1,000 a day for about 1 to 2 lb a week at first, without going below 1,200 (women) or 1,500 (men) — Harvard Health.
How many calories do I naturally burn every day?
That's your TDEE. Even at complete rest you burn your resting metabolism — 1,780 of the worked example's 2,932.
Sources
- National Academies (2023), Dietary Reference Intakes for Energy, Table S-1
- National Academies (2023), chapter 7, activity levels
- Mifflin MD et al., American Journal of Clinical Nutrition 1990
- NIDDK, model appendix for Hall et al. 2011
- Hall KD et al., The Lancet 2011 (NIH author manuscript)
- Harvard Health Publishing, Calorie counting made easy
- CDC, Adult BMI categories