TDEE Calculator
Total daily energy expenditure is everything you burn in a day. The first panel predicts it the usual way, from an equation and an activity factor. The second does something most calculators do not: it works your real expenditure out backwards from what you actually ate and what the scale actually did — no multiplier guessed at.
Mifflin-St Jeor BMR of 1,649 kcal, multiplied by 1.55 for your activity level.
Measured from your data
- Daily balance
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- Your real multiplier
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Everything is calculated in your browser. Nothing you type leaves this page.
What makes up your daily burn
These are ranges, not a personalised split, and deliberately so. Non-exercise activity varies by up to 2,000 kcal a day between people of similar size, so any calculator carving your day into exact slices is inventing the precision. What the ranges are good for is seeing where the leverage actually is — and it is not where most people look.
| Component | Share | What it is |
|---|---|---|
| Basal metabolic rateBMR | 60–70% | Keeping you alive at rest. The largest and least changeable share. |
| Thermic effect of foodTEF | ~10% | The cost of digesting what you eat. Protein costs the most to process. |
| Non-exercise activityNEAT | 15–30% | Fidgeting, standing, walking about. Varies enormously between people and falls during a deficit. |
| Exercise activityEAT | 0–15% | Deliberate training. Usually the smallest slice, despite getting the most attention. |
Why the tracking window has to be long
Bodyweight moves for reasons that have nothing to do with fat: water, glycogen, gut contents, salt, the time of day you stepped on the scale. Over a short window that noise dwarfs the signal. This table shows how far wrong a mere half-kilogram of measurement error throws the daily figure, purely as a function of how long you tracked.
| Tracked for | Error from ±0.5 kg |
|---|---|
| 1 week | ±550 kcal/day |
| 2 weeks | ±275 kcal/day |
| 4 weeks | ±138 kcal/day |
| 8 weeks | ±69 kcal/day |
| 12 weeks | ±46 kcal/day |
At one week, half a kilo of water is a 550 kcal-a-day error — larger than the deficit most people are aiming for, which is how a perfectly good plan gets abandoned in its second week. At eight weeks the same error is under 70. Weigh yourself under identical conditions, use a weekly average rather than a single reading, and track for at least a month before concluding anything.
The arithmetic, both directions
Predicted TDEE = BMR × activity factor
Measured (intake − TDEE) × days = weight change × 7,700 kcal/kg
so TDEE = intake − (weight change × 7,700) / days
Your real activity factor = measured TDEE / BMRThe prediction stacks two population estimates: a BMR equation accurate to about 10% for most people, multiplied by an activity factor that is cruder still. The measurement uses neither. It asks only that energy is conserved, which it is, and that your intake logging and your scale are honest — which is where its own error lives.
Where the measured figure goes wrong
Under-reporting is the dominant error, and it only runs one way: people typically log 10 to 30% less than they eat, through forgotten extras, eyeballed portions and untracked cooking oil. That makes measured TDEE read low. If your measured figure comes out far below the prediction and you are not losing weight at the rate that implies, suspect the food log before you suspect your metabolism.
What this cannot tell you
Neither figure is a measurement in the laboratory sense. Indirect calorimetry and doubly labelled water exist for a reason, and a prediction equation is the wrong tool where a thyroid disorder, pregnancy, a medication or a diagnosed metabolic condition is in play — none of which is modelled here.
Your TDEE is also not a constant. It falls as you lose weight, by more than the size change alone predicts, and it moves with sleep, illness, stress and season. Treat any figure on this page as true for this month, and recalculate as you go.
Medical disclaimer. This calculator is for general information and education only. It is not medical advice, not a diagnosis, and not a substitute for professional care. Do not use these figures to plan intake for a child, during pregnancy or breastfeeding, or alongside an eating disorder or a diagnosed metabolic condition.Speak to a doctor or a registered dietitian before making significant dietary changes.Last reviewed .
Frequently asked questions
What is TDEE?
Total Daily Energy Expenditure is everything you burn in a day: your basal metabolic rate, which is 60 to 70% of it, the thermic effect of digesting food at roughly 10%, and everything you move — deliberate exercise plus all the incidental activity that is not exercise. It is the figure every calorie target is built from, because eating at it holds your weight steady by definition.
How do I find my real TDEE rather than an estimate?
Track what you eat for at least two weeks, weigh yourself under the same conditions at the start and end, and work backwards from energy balance. If you averaged 2,200 kcal a day for 4 weeks and lost 1.2 kg, you spent about 2,530 a day — that 1.2 kg is roughly 9,240 kcal you were short by, or 330 a day. At a 70 kg, 175 cm, 30-year-old man's resting rate that works out to a "moderately active" lifestyle. The measured panel on this page does exactly this arithmetic, and it beats any equation because it measures you rather than a population.
Why does my measured TDEE differ from the estimate?
Almost always because the activity multiplier is wrong, which is unsurprising — it is a single number standing in for everything you do in a day. Non-exercise activity alone varies by hundreds of calories between people of similar size. Under-reported intake is the other common cause, and it runs in one direction: people typically log 10 to 30% less than they actually eat, which makes measured TDEE read lower than it really is.
How accurate is the activity multiplier?
It is the weakest step in the whole calculation, weaker than the BMR equation it multiplies. Most people overestimate how active they are. When two levels both sound like you, take the lower one, then correct from real weight change over two to three weeks rather than trusting the first figure.
How long should I track before trusting the number?
Two weeks is the minimum and four is better. Under a fortnight, ordinary swings in water and gut contents swamp the actual fat change: a single kilogram of glycogen-bound water shifting over ten days reads as a 770 kcal-a-day error that is not real. Longer windows average that noise out, which is the whole reason the table on this page exists.
What is NEAT and why does it matter so much?
Non-exercise activity thermogenesis is everything you burn moving that is not deliberate training — walking, standing, fidgeting, gesturing, being restless. It is the single most variable component of expenditure, differing by up to 2,000 kcal a day between individuals of similar size, and it falls automatically during a prolonged deficit without you noticing. That silent reduction is a large part of why weight loss stalls.
Why has my TDEE dropped since I lost weight?
A smaller body costs less to move and to maintain, so basal rate falls with mass. Adaptive thermogenesis adds a further reduction beyond what the size change alone predicts, and spontaneous movement usually declines during a deficit. Recalculating at your new weight every few kilograms, rather than holding the original figure, is what keeps progress going.
Does exercise add as much as I think?
Usually less. Deliberate training is typically the smallest of the four components, often under 15% of the total even for people who train regularly, and fitness trackers tend to overstate it. There is also compensation: a hard session often reduces incidental movement for the rest of the day, so the net addition is smaller than the session alone suggests.
Which BMR equation does the estimate use?
Mifflin-St Jeor, the current clinical default. If you know your body fat percentage, the BMR calculator on this site offers Katch-McArdle and Cunningham as well, which work from lean mass and are more accurate for builds far from average. The measured panel here does not use any equation at all, which is precisely its advantage.
Is my data saved or uploaded anywhere?
No. Every calculation runs in your browser. Nothing you type is uploaded, stored, or logged, and the page keeps working offline once loaded. If you share the page URL after calculating, the figures you entered are in the link — clear the query string first if you would rather not pass them on.