TDEE Calculator

TDEE stands for total daily energy expenditure. It counts the calories you burn in a day, from rest, movement and digestion. The tool works in two steps: it estimates your resting burn first, then multiplies that by an activity factor.

Formulas

How it works, step by step

1. First, the calculator converts your height and weight to centimeters and kilograms.
2. Then it applies the Mifflin-St Jeor equation for your sex to estimate your resting burn.
3. Next, it multiplies that number by the factor for your activity level.
4. Finally, it rounds the result to the nearest 10 calories.

Worked example

A 30-year-old man who is 180 cm tall and weighs 80 kg has a resting burn of 1,780 calories. With moderate exercise the factor is 1.55, so his TDEE comes to about 2,759 calories, which rounds to 2,760.

Accuracy and limits

Mifflin and colleagues built the equation from 498 healthy adults aged 19 to 78, and they measured each person's resting burn with indirect calorimetry. A 2005 systematic review found that it landed within 10% of measured rate for more people than the other common equations. The review also warned that errors for one person can still be large.

The activity factors rest on convention, so they carry more doubt than the resting equation. When women in one study reported their own activity, two common equations overestimated total energy use by about 200 to 300 calories a day. If you sit between two levels, pick the lower one.

The FAO, WHO and UN University report uses the same idea. It puts a sedentary or light lifestyle at 1.40 to 1.69 times resting burn.

• The equation uses weight, height, age and sex. It cannot see your muscle mass or your medical history.
• The studies included few older adults and few people from some ethnic groups, so the review urged extra caution for them.
• Before you rely on the result, check it against two to three weeks of real weight data.

Sources

1. Mifflin MD, St Jeor ST, Hill LA, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241-247. Used for: The Mifflin-St Jeor equation and the 498 adults it came from.
2. Frankenfield D, Roth-Yousey L, Compher C. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review. J Am Diet Assoc. 2005;105(5):775-789. Used for: How often each common equation lands within 10% of measured resting rate.
3. Ramirez-Marrero FA, Edens KL, Joyner MJ, Curry TB. Predicted vs. actual resting energy expenditure and activity coefficients: post-gastric bypass, lean and obese women. Obes Control Ther. 2014;1(2):1-7. Used for: The 1.2 to 1.9 activity multipliers and how self-reported activity can overshoot.
4. FAO, WHO and UNU. Human energy requirements: report of a Joint FAO/WHO/UNU Expert Consultation. FAO Food and Nutrition Technical Report Series No. 1. Rome; 2004 (section on adult energy requirements). Used for: Physical activity levels as a multiple of resting burn.

Sources and math last reviewed: November 4, 2026.