TDEE Calculator — Step-by-Step Solutions

The TDEE Calculator estimates your Total Daily Energy Expenditure — the number of calories you burn each day including exercise and daily activities. It uses both the Mifflin-St Jeor and Harris-Benedict equations with your activity level to provide accurate estimates.

Four modes let you calculate TDEE with each formula individually, compare both side by side, or see a detailed breakdown by activity level. Pairs with our Calorie and BMR calculators for complete nutritional planning.

Age

Gender

Weight (kg)

Height (cm)

Activity Level

Your calculations will appear here

How to Use the TDEE Calculator

Choose a formula view: Mifflin-St Jeor, Harris-Benedict, Compare Both, or Activity Breakdown, which lists maintenance calories for every activity level.
Enter your age and sex, switch between Metric and Imperial units, and enter your weight and height.
Select your activity level honestly: from sedentary (little or no exercise) to very active (intense daily exercise). Over-estimating activity is the most common reason the result is too high.
Your TDEE is shown in kilocalories per day along with your BMR. These are estimates and not medical advice.

Formula and Theory

Total daily energy expenditure (TDEE) is the number of calories you burn in a day: the energy at rest (BMR), plus the energy for digesting food, everyday movement and exercise. Eating about your TDEE keeps weight roughly stable; eating less or more shifts it over time.

The calculation is TDEE = BMR x activity factor. The factors used here are 1.2 for sedentary, 1.375 for lightly active (1-3 days of exercise per week), 1.55 for moderately active (3-5 days), 1.725 for active (6-7 days) and 1.9 for very active (intense daily exercise or a physical job).

BMR comes from the Mifflin-St Jeor equation, 10 x weight (kg) + 6.25 x height (cm) - 5 x age, then + 5 for men or - 161 for women, or from the revised Harris-Benedict equation. Compare Both shows the two results so you can see the spread.

The activity factors are broad averages, not measurements, so the result can be off by several hundred calories for an individual. Use it as a starting point and adjust from real-world changes in weight. It is an estimate, not medical advice.

Worked Examples

Example 1: Lightly active woman

Problem: A 35-year-old woman, 65 kg, 165 cm, exercises 1-3 days a week. Find her TDEE with Mifflin-St Jeor.

Solution: BMR = 10 x 65 + 6.25 x 165 - 5 x 35 - 161 = 650 + 1,031.25 - 175 - 161 = 1,345.25. Lightly active factor = 1.375. TDEE = 1,345.25 x 1.375 = 1,849.7.

Answer: About 1,850 kcal/day (BMR 1,345)

Example 2: The same woman at a moderate activity level

Problem: She moves to planned exercise 3-5 days a week (factor 1.55).

Solution: TDEE = 1,345.25 x 1.55 = 2,085.1. That is 2,085.1 - 1,849.7 = 235.4 kcal more than at the lightly active level.

Answer: About 2,085 kcal/day

Example 3: Comparing the two formulas

Problem: For the same woman at the lightly active level, what does Harris-Benedict give?

Solution: Harris-Benedict BMR = 447.593 + 9.247 x 65 + 3.098 x 165 - 4.330 x 35 = 447.593 + 601.055 + 511.17 - 151.55 = 1,408.27. TDEE = 1,408.27 x 1.375 = 1,936.4.

Answer: About 1,936 kcal/day, roughly 86 kcal above the Mifflin-St Jeor result

Example 4: The range between the lowest and highest activity levels

Problem: Same woman, sedentary (factor 1.2) against very active (factor 1.9).

Solution: Sedentary: 1,345.25 x 1.2 = 1,614.3. Very active: 1,345.25 x 1.9 = 2,556.0. The gap between the two levels is 2,556.0 - 1,614.3 = 941.7 kcal a day, which is why choosing the level honestly matters.

Answer: About 1,614 kcal/day sedentary and 2,556 kcal/day very active

Frequently Asked Questions

What does TDEE stand for?

Total daily energy expenditure: the total number of calories you burn in a day, including rest, movement, exercise and digestion.

How do I choose my activity level?

Base it on your typical week, not your best one. Sedentary means desk work and little exercise; moderately active means planned exercise 3-5 days a week. When in doubt pick the lower level.

How accurate is a TDEE calculator?

It is an estimate. Individual energy use can differ from the formula by several hundred calories. Track your weight over a few weeks to see whether the number matches your reality, and adjust.

How is TDEE different from BMR?

BMR is the energy your body needs at rest. TDEE multiplies it by an activity factor, so it is always higher, by 20% for sedentary people and up to 90% for very active ones.

Should I eat my TDEE to lose weight?

Eating at TDEE roughly maintains weight. Changing intake relative to it is a personal decision that depends on health; this is not medical advice, so check with a doctor or dietitian first. The Calorie Calculator shows the effect of different targets.

Why do the two formulas give different TDEE?

Because their BMR estimates differ, and the same activity factor multiplies the difference. Mifflin-St Jeor and Harris-Benedict were developed from different data.