TDEE (total daily energy expenditure) is an estimate of the total calories you burn per day. It combines your basal metabolic rate — the energy your body uses at rest — with an activity multiplier that accounts for exercise and daily movement.

Which TDEE formula is most accurate?

For most people the Mifflin–St Jeor equation is the best-validated starting point, which is why this calculator uses it by default. If you know your body-fat percentage from a reliable measurement, the Katch–McArdle equation may give a better estimate because it works from lean mass.

What is the difference between BMR and TDEE?

BMR (basal metabolic rate) is the energy your body uses at complete rest to keep basic functions running. TDEE is BMR multiplied by an activity factor, so it estimates everything you burn in a normal day, including exercise and everyday movement.

How do I use TDEE to lose or gain weight?

Your TDEE is an estimate of maintenance calories. Eating consistently below it tends to produce weight loss and eating above it tends to produce weight gain. Because it is only an estimate, track your weight over a few weeks and adjust intake based on what actually happens.

Which activity level should I pick?

Choose based on your whole week, not your best day. Most people with desk jobs who train three to five times a week fall under moderate activity. If your weight is not moving the way the estimate predicts, adjust the activity level down or up rather than assuming the formula is wrong.

How accurate is a TDEE calculator?

Prediction equations are typically within about 10% of measured values for most healthy adults, but individual results vary with genetics, body composition and daily movement. Treat the number as a starting estimate to refine with real-world tracking, not a precise measurement.

TDEE Calculator — Total Daily Energy Expenditure

Estimate the calories you burn per day from your stats and activity level, using peer-reviewed equations.

Nutrition
3 cited sources
Runs in your browser

Your estimated daily energy expenditure

2,711 kcal/day

of which BMR

1,749 kcal

We estimate you burn around 2,711 kcal per day at your selected activity level, of which 1,749 kcal is your estimated basal metabolic rate — the energy your body uses at complete rest. These are estimates, not measurements: use them as a starting point and adjust based on how your weight actually responds over a few weeks.

Results save to this device only — private, automatic.

Estimated daily energy expenditure at each activity level
Activity level	Estimate (kcal/day)
Sedentary — little or no exercise (×1.2)	2,099
Lightly active — exercise 1–3 days a week (×1.375)	2,405
Moderately active — exercise 3–5 days a week (×1.55)	2,711
Very active — hard exercise 6–7 days a week (×1.725)	3,017
Extremely active — hard daily exercise or a physical job (×1.9)	3,323

Methodology

This calculator estimates your total daily energy expenditure (TDEE) in two steps: it first estimates your basal metabolic rate (BMR), then multiplies it by an activity factor.

By default, BMR is estimated with the Mifflin–St Jeor equation, published in the American Journal of Clinical Nutrition in 1990 and repeatedly found to be the most reliable of the common prediction equations for healthy adults:

Sex	Equation (kcal/day)
Men	`BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) + 5`
Women	`BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) − 161`

This is the simplified form proposed for practice in the original paper; the paper’s full regression coefficients (9.99 for weight and 4.92 for age) round to the values above.

If you know your body-fat percentage from a reliable measurement, you can switch to the Katch–McArdle equation, which works from fat-free mass (FFM) instead of total weight:

BMR = 370 + 21.6 × FFM (kg), where FFM = weight × (1 − body fat ÷ 100)

The revised Harris–Benedict equation (Roza & Shizgal, 1984) is also available as a toggle for comparison — it is an older model that tends to estimate slightly higher than Mifflin–St Jeor for most people:

Sex	Equation (kcal/day)
Men	`BMR = 88.362 + 13.397 × weight + 4.799 × height − 5.677 × age`
Women	`BMR = 447.593 + 9.247 × weight + 3.098 × height − 4.330 × age`

Your BMR is then multiplied by a standard activity factor — 1.2 (sedentary), 1.375 (lightly active), 1.55 (moderately active), 1.725 (very active) or 1.9 (extremely active) — to estimate the total calories you burn in a normal day.

Interpreting your result

Your TDEE is an estimate of maintenance calories: eat around this amount and your weight should stay roughly stable. A sustained intake below it tends to produce weight loss; a sustained intake above it tends to produce weight gain. Because every figure here is an estimate, the most useful next step is to track your weight for two to four weeks and adjust intake based on what actually happens, rather than treating the number as exact.

Limitations

Prediction equations describe the average person of your size, age and sex. Individual BMR commonly varies by up to about 10% either side of the prediction, and more in people with very high or very low muscle mass.
Activity factors are the biggest source of error. Most people overestimate their activity level; if in doubt, pick the lower option.
Mifflin–St Jeor was derived in healthy, mostly non-athletic adults. For very muscular people, Katch–McArdle with a measured body-fat percentage is usually the better choice.
Energy expenditure adapts as you diet (adaptive thermogenesis), so a deficit that works initially will slowly shrink; recalculate as your weight changes.

Sources

Pull the receipts — 3 cited sources

FitTools · sources

Every formula cited ✓

Frequently asked questions

What is TDEE?: TDEE (total daily energy expenditure) is an estimate of the total calories you burn per day. It combines your basal metabolic rate — the energy your body uses at rest — with an activity multiplier that accounts for exercise and daily movement.
Which TDEE formula is most accurate?: For most people the Mifflin–St Jeor equation is the best-validated starting point, which is why this calculator uses it by default. If you know your body-fat percentage from a reliable measurement, the Katch–McArdle equation may give a better estimate because it works from lean mass.
What is the difference between BMR and TDEE?: BMR (basal metabolic rate) is the energy your body uses at complete rest to keep basic functions running. TDEE is BMR multiplied by an activity factor, so it estimates everything you burn in a normal day, including exercise and everyday movement.
How do I use TDEE to lose or gain weight?: Your TDEE is an estimate of maintenance calories. Eating consistently below it tends to produce weight loss and eating above it tends to produce weight gain. Because it is only an estimate, track your weight over a few weeks and adjust intake based on what actually happens.
Which activity level should I pick?: Choose based on your whole week, not your best day. Most people with desk jobs who train three to five times a week fall under moderate activity. If your weight is not moving the way the estimate predicts, adjust the activity level down or up rather than assuming the formula is wrong.
How accurate is a TDEE calculator?: Prediction equations are typically within about 10% of measured values for most healthy adults, but individual results vary with genetics, body composition and daily movement. Treat the number as a starting estimate to refine with real-world tracking, not a precise measurement.

Embed this calculator

Free to embed with the attribution link intact.

<iframe src="https://tools.fit/embed/tdee-calculator" width="440" height="420" style="border:0;max-width:100%" title="Calculator by FitTools" loading="lazy"></iframe>

Written and reviewed by Mathew Beale — MSc Biotechnology, University of Reading.

Last reviewed: 21 July 2026

Macro Calculator — Protein, Fat & Carb Targets
Free macro calculator: set protein by bodyweight (1.6–2.2 g/kg, per Morton et al. 2018), choose a fat percentage, and get gram and calorie targets for each macro.
Calorie Deficit Calculator — Weight-Loss Timeline
Free calorie deficit calculator: estimate weekly weight loss and a timeline to your goal using the 7,700 kcal/kg heuristic, with a safety cap at 25% of your TDEE.
BMI Calculator — Body Mass Index & WHO Category
Free BMI calculator with WHO categories (underweight to obesity class III), metric and imperial inputs, and an honest explanation of BMI's limits for muscular and athletic builds.

Glossary:

Supplements:

Whey protein

Food reference:

Reference tables:

Daily Protein Targets by Bodyweight