TDEE Calculator

What Is TDEE?

TDEE stands for Total Daily Energy Expenditure — the total number of calories your body burns in a 24-hour period. It's made up of four components:

• BMR (Basal Metabolic Rate) — energy used for basic life-sustaining functions like breathing, circulation, and cell production. This accounts for 60–75% of your total burn.
• TEF (Thermic Effect of Food) — energy used to digest, absorb, and process nutrients. Roughly ~10% of total calories.
• NEAT (Non-Exercise Activity Thermogenesis) — energy burned through daily movement that isn't formal exercise: walking, fidgeting, standing, household chores.
• EAT (Exercise Activity Thermogenesis) — energy burned through deliberate exercise. Together with NEAT, activity accounts for 15–30% of TDEE.

TDEE vs BMR — What's the Difference?

BMR is what you'd burn if you lay in bed all day doing absolutely nothing — no eating, no moving, no scrolling your phone. TDEE is your BMR plus everything else: walking to the kitchen, your workout, even digesting food.

The distinction matters because most people accidentally eat at their TDEE when they think they're eating at their BMR. If your BMR is 1,600 but your TDEE is 2,200, eating 1,600 kcal creates a 600-calorie deficit — which may be too aggressive for some people.

Understanding Activity Multipliers

Your TDEE is calculated by multiplying your BMR by an activity factor. Choosing the right level is critical — most people overestimate their activity.

How to Pick Your Multiplier Without Overshooting

The multiplier is the weakest link in the whole calculation. Your BMR comes from measured inputs — weight, height, age, sex. The activity factor comes from a dropdown you fill in about yourself, and one step between adjacent options is worth hundreds of calories a day.

The five levels, translated into hours and sessions rather than adjectives:

• 1.2 — Sedentary. Under about 5,000 steps a day and no training. Desk work, a car commute, evenings sitting down. Most office workers who don't train belong here even if it feels harsh.
• 1.375 — Lightly active. Roughly 5,000–7,500 steps plus one to three sessions a week of 45–60 minutes. This is where the average committed gym member actually sits.
• 1.55 — Moderately active. 7,500–10,000 steps and four to five hard sessions a week, or a job that keeps you upright for part of the day.
• 1.725 — Very active. Six or seven sessions a week, usually 8–12 hours of training, on top of a day that isn't spent in a chair.
• 1.9 — Extra active. Manual work for eight hours plus training, or two sessions a day. Construction, farm work, military selection, a competitive endurance block.

The single most common error: a desk job with three gym sessions a week is lightly active (1.375), not moderately active. Three one-hour resistance sessions at roughly 3.5 METs cost an 80 kg person about 294 kcal each (Ainsworth et al., 2011 Compendium of Physical Activities) — around 880 kcal a week, or 126 kcal a day once you spread it across seven days. Jumping from 1.2 to 1.55 on a 1,742 kcal BMR adds 610 kcal a day. You'd need roughly five times that training to earn the jump.

Worked Example: One Person, Five Multipliers

Sarah is 34, 168 cm and 70 kg. The Mifflin-St Jeor equation gives her resting burn first, before any activity multiplier touches it.

Now apply each activity factor to that same 1,419 kcal:

Sarah's answer ranges across 993 kcal depending on one dropdown. The gap between lightly active and moderately active is 248 kcal on its own. If she trains three evenings a week, sits at a desk, picks 1.55 and eats to that number, she runs a 248 kcal surplus. At roughly 7,700 kcal per kilogram of body mass, that's about a kilo of fat every 31 days — gained while eating what a calculator called maintenance.

TDEE Reference Tables by Body Weight

Use these to sanity-check the number above. Both grids use Mifflin-St Jeor for a 35-year-old, holding height and age fixed so only weight moves.

Men, 178 cm, age 35

Women, 165 cm, age 35

All values in kcal per day, rounded. Adjust for your own build: every 10 cm of height moves BMR by 62.5 kcal, and every decade of age by 50 kcal. For a fuller walkthrough of daily targets, see how many calories you should eat per day.

NEAT: Why Identical Workouts Produce Different Numbers

Two people train the same three days, weigh the same, eat the same, and still hold maintenance calories 400 kcal apart. The difference lives in the 23 hours they aren't training.

Levine and colleagues (Science, 2005) fitted lean and mildly obese volunteers with posture sensors. Nobody in the study did formal exercise. The obese group sat around 2.5 hours more each day, and that posture difference alone came to roughly 352 kcal daily.

An earlier trial from the same group (Levine et al., Science, 1999) overfed 16 adults by 1,000 kcal a day for eight weeks. Their NEAT responses ranged from −98 to +692 kcal a day, and that spread predicted who stored the surplus as fat. Same food, same protocol, a ten-fold difference in the body's reply.

A step count beats a dropdown because your phone counts steps instead of estimating them. Walking costs roughly 0.5 kcal per kilogram of body weight per kilometre. For an 80 kg person, the distance between 4,000 and 12,000 steps is about 6 km, or close to 250 kcal — every day, whether or not the gym happens. Stack that on top of posture differences and the 400 kcal gap stops being mysterious. It also explains why "slow metabolism" usually turns out to be low daily movement.

MacroLog reads step count and active energy from Apple Health and Google Health Connect, and treats both as information only. They're shown to you; they never change your calorie budget. Wearable energy estimates carry error of their own, so letting them top up a daily target would stack one estimate on another. When your step count genuinely doubles for a month, you change the goal yourself.

When the Scale Disagrees With Your TDEE

Mifflin-St Jeor predicts measured resting metabolic rate within 10% for about 82% of adults (Frankenfield et al., 2005, reviewing predictive equations against indirect calorimetry). For the remaining 18%, the miss can exceed 300 kcal before the activity multiplier adds its own error on top.

After three or four weeks of consistent logging you can stop guessing. Don't re-run the formula with a friendlier multiplier — read your maintenance off your own data:

• Average your intake. Take the mean of every logged day across weeks two, three and four. Drop week one; logging accuracy improves quickly and the first week is almost always an undercount.
• Average your weight. Weigh every morning, then compare the mean of week two against the mean of week four. Single readings swing 1–2 kg on sodium, glycogen and gut contents, which is why the scale lies day to day.
• Convert the trend. A kilogram of body mass is roughly 7,700 kcal. Gained 0.4 kg over 28 days? That's about 110 kcal a day above maintenance (0.4 × 7,700 ÷ 28).
• Subtract. If you averaged 2,400 kcal while gaining that 0.4 kg, your real TDEE sits near 2,290 — whatever the calculator printed.

Two cautions on the arithmetic. Self-reported intake is the fragile input: Lichtman et al. (New England Journal of Medicine, 1992) found volunteers who called themselves diet-resistant under-reported their food by 47% and over-reported their exercise by 51%. And if you've held a deficit for months, part of the gap is adaptive thermogenesis — the body spending less on the same tasks (Rosenbaum & Leibel, 2010) — which cutting calories further does not fix. That situation is a plateau problem, not a formula problem.

How to Use Your TDEE

Once you know your TDEE, you can set a calorie target based on your goal:

• Maintain weight: eat at your TDEE.
• Lose weight: eat 300–500 kcal below your TDEE. A deficit larger than 1,000 kcal/day is rarely sustainable and risks muscle loss.
• Gain muscle: eat 200–500 kcal above your TDEE (a "lean bulk") to support muscle growth while minimising fat gain.

TDEE Calculator FAQ

• Is a TDEE calculator accurate?

  The resting part is solid: Mifflin-St Jeor lands within 10% of measured RMR for about 82% of adults (Frankenfield et al., 2005). On a 2,400 kcal target that's a ±240 kcal window. The activity multiplier is where error compounds, because you choose it. Treat the output as a starting point and correct it against three to four weeks of weight data.

• I have a desk job and lift three times a week — which activity level?

  Lightly active, 1.375. Three hours of training a week works out to roughly 120–150 kcal a day once spread across seven days. Moderately active (1.55) describes someone training five or more days and clearing 7,500 steps on top of that.

• Should I eat back the calories my watch says I burned?

  Not if your TDEE already includes an activity multiplier — you'd be counting the same workout twice. Wrist devices also overstate energy cost badly. Shcherbina et al. (Journal of Personalized Medicine, 2017) tested seven consumer trackers and found none met a 20% error threshold for energy expenditure, with median errors from 27% to 93%. Pick one method and stay with it.

• Why did my TDEE drop after I lost weight?

  A smaller body costs less to run. Losing 10 kg cuts Mifflin-St Jeor BMR by exactly 100 kcal, and TDEE by 120–190 kcal depending on your multiplier, since you also carry less mass through every step. Sustained dieting lowers expenditure beyond what the weight change alone predicts (Rosenbaum & Leibel, 2010).

• How often should I recalculate my TDEE?

  Every 5 kg of weight change, or whenever your training load or job changes for more than a month. Recalculating weekly is noise — the inputs barely move, so the output barely moves with them.

• Is TDEE the same as maintenance calories?

  Yes, seen from two sides. TDEE is what your body spends in 24 hours; maintenance calories is what you eat to match that spend. The number is identical, and eating at it holds your weight steady.

• Do I add my workouts on top of my TDEE?

  No. The multiplier already contains them, so adding a session again is the most common double-count in calorie tracking. If you prefer logging exercise separately, set the multiplier to 1.2 and add each session's real cost — then hold yourself to honest numbers.

• Why do two TDEE calculators give me different numbers?

  Different equations. For an 80 kg, 178 cm, 35-year-old man, the revised Harris-Benedict equation returns about 1,816 kcal against Mifflin-St Jeor's 1,742 — a 74 kcal gap before any multiplier. Katch-McArdle uses lean mass instead of total weight and needs a body-fat figure. Frankenfield's 2005 review rated Mifflin-St Jeor most accurate across non-obese and obese adults, which is why this page uses it. The difference between BMR and TDEE accounts for the rest.