What is TDEE?
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns over the course of a day. It is the single most important number in nutrition planning - your TDEE is your true maintenance calorie level. Eat consistently below it and you lose weight; eat consistently above it and you gain weight; eat at it and your weight holds steady.
TDEE is composed of four distinct components that together account for all the energy your body uses. To understand how TDEE relates to just your resting metabolism, see our BMR Calculator.
The calories burned at complete rest to sustain vital organ function - heartbeat, breathing, temperature regulation, cellular repair.
Calories burned during intentional structured exercise: gym sessions, running, cycling, swimming.
Calories burned through all daily movement that isn't deliberate exercise: walking, fidgeting, posture, household tasks.
The energy cost of digesting, absorbing, and processing food. Protein has the highest TEF (20–35%), making high-protein diets metabolically advantageous.
How TDEE Differs from BMR
BMR and TDEE are related but distinct. BMR is a theoretical baseline - the calories you'd burn if you stayed in bed motionless all day. TDEE is your real-world energy expenditure. The gap between the two can be substantial depending on how active you are.
| Metric | Definition | Typical % of TDEE |
|---|---|---|
| BMR | Calories burned at complete rest | 60–75% |
| TDEE | Total daily calorie burn (all activity) | 100% |
| Deficit target | TDEE minus 300–500 cal | ~80–85% |
| Surplus target | TDEE plus 200–400 cal | ~103–115% |
Formula Explanations
This calculator uses two validated formulas depending on whether you provide body fat percentage.
Published in the American Journal of Clinical Nutrition. Validated as the most accurate general-population BMR equation in a 2005 JADA meta-analysis covering 2,919 subjects.
Uses lean body mass (weight × [1 − body fat %]). More accurate for athletes, muscular individuals, and anyone whose body composition deviates significantly from average. Lean mass is a far stronger predictor of BMR than total weight.
In both cases, the resulting BMR is multiplied by an activity factor (1.2–1.9) to produce TDEE. The activity factor is the most impactful variable - a wrong selection of even one tier can shift TDEE by 150–300 calories, enough to completely undermine a weight management plan.
Using TDEE for Weight Management
- Target a deficit of 300–500 cal/day below TDEE for sustainable ~1 lb/week loss
- Do not eat below your BMR without medical supervision
- Prioritize protein (0.8–1g/lb) to preserve muscle during the deficit
- Recalculate every 4–6 weeks as your weight and TDEE decrease
- Use the Calorie Deficit Calculator to model your fat loss timeline
- Eat at your TDEE to keep weight stable
- Allow ±100–150 cal daily flexibility - weekly averages matter more than daily precision
- Continue to recalculate if your activity level changes significantly
- Monitor weight weekly, not daily, to filter out water retention noise
- Add 200–400 cal/day above TDEE for lean muscle gain with minimal fat
- Natural lifters can gain 0.25–0.5 lb of muscle per week maximum
- Larger surpluses (1,000+ cal/day) primarily add fat, not muscle
- Pair with the Macro Calculator and Protein Calculator for precise nutrition targets
Sources & References
- Mifflin MD, St Jeor ST, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241-247.
- Frankenfield D, et al. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults. J Am Diet Assoc. 2005;105(5):775-789.
- Katch V, McArdle WD. Prediction of body density from simple anthropometric measurements in college-age men and women. Hum Biol. 1973;45(3):445-454.
- American College of Sports Medicine. ACSM's Guidelines for Exercise Testing and Prescription. 11th ed. Lippincott Williams & Wilkins; 2021.