What is TDEE, and how is it calculated?
Total daily energy expenditure, in plain terms: what goes into it, how calculators estimate it, and where the estimate goes wrong.
Last reviewed October 15, 2026
TDEE, or total daily energy expenditure, is the number of calories you burn in a whole day.[4] Calculators estimate it by working out your resting burn and multiplying it by a factor for how active you are.[1] It is a starting estimate, so the useful version is the one you check against your weight over a few weeks.[5]
Key takeaways
- TDEE is your total daily energy expenditure: everything you burn in a day, at rest and moving.[4]
- Resting burn is the biggest part, typically 60 to 70 percent of the total.[4]
- Calculators estimate resting burn with an equation such as Mifflin-St Jeor, then multiply it by an activity factor.[1]
- Mifflin-St Jeor landed within 10% of measured resting burn for 82% of adults in one study, and less often in people with obesity.[3]
- Treat any TDEE as a first guess. The National Academies plans intake by estimating, then watching body weight over time and adjusting.[5]
What makes up your daily burn
Your daily burn has three parts. Resting burn, the energy that keeps you alive at rest, typically accounts for 60 to 70 percent of the total.[4] Digesting food takes about 10 percent.[4] Movement varies the most, from 15 percent for sedentary people up to 50 percent for physically active people.[4]
- Total daily energy expenditure (TDEE)
- All the calories you burn in a day: resting burn, digestion and movement added together.[4]
TDEE versus BMR
BMR (basal metabolic rate) and resting metabolic rate (RMR), also called resting energy expenditure, both describe the energy you use at rest. Resting energy expenditure runs about 10% higher than BMR.[4] Both are only the resting part of the day. TDEE adds digestion and movement.[4]
The Mifflin-St Jeor equation is one way to estimate resting burn. It came from resting measurements of 498 healthy adults.[1] A review of the four most used equations found Mifflin-St Jeor the most reliable of them.[2]
| Resting burn per day | |
|---|---|
| Men | 10 × weight + 6.25 × height − 5 × age + 5[1] |
| Women | 10 × weight + 6.25 × height − 5 × age − 161[1] |
How activity factors turn BMR into TDEE
The shortcut multiplies resting burn by one number for how active you are. Dalia uses five activity factors for a starting estimate: sedentary (desk job, little exercise) 1.2, lightly active (1 to 2 workouts a week) 1.375, moderately active (3 to 4) 1.55, very active (5 or more) 1.725, and athlete (hard training every day) 1.9.
These factors are a method, not a measurement. An expert report from the FAO, WHO and UNU writes a day's energy need as a multiple of BMR.[7] It puts a sedentary or light lifestyle at 1.40 to 1.69, an active one at 1.70 to 1.99, and a vigorous one at 2.00 to 2.40.[7]
The National Academies uses separate equations for four activity levels instead.[6] It calls picking the right level a critical step.[5]
Worked example
TDEE for one person
Take a 30-year-old man who is 5 ft 10 in (177.8 cm) tall, weighs 180 lb (81.6 kg) and works out 3 to 4 times a week. These are the same steps, constants and rounding the Dalia app uses.
Resting burn (Mifflin-St Jeor, men)
10 × 81.65 + 6.25 × 177.8 − 5 × 30 + 5
1,783 cal
Activity factor (moderately active)
1,782.7 × 1.55
2,763 cal
Estimated TDEE
2,763 calories a day
| Activity level | Factor | Estimated TDEE |
|---|---|---|
| Sedentary | 1.2 | 2,139 cal |
| Lightly active | 1.375 | 2,451 cal |
| Moderately active | 1.55 | 2,763 cal |
| Very active | 1.725 | 3,075 cal |
| Athlete | 1.9 | 3,387 cal |
You can run your own numbers in the TDEE calculator, which shows each step with your inputs.
How accurate is a TDEE estimate?
The resting part is the better-tested half. In 337 adults, Mifflin-St Jeor came within 10% of measured resting burn 82% of the time.[3] Accuracy was lower in people with obesity, 75% against 87% without.[3] The review of the common equations warns that older adults and US ethnic minorities were underrepresented in building and testing them.[2]
The activity level is a guess too. The National Academies calls that choice critical.[5] Food logs miss things: when people write down what they eat, they most often leave some out.[5] If your weight holds steady, you are eating about what you need.[5] So a few steady weeks at a known intake is a good check on any formula.
TDEE also moves as your weight does. Energy use adapts as weight comes off, and body weight responds to eating less slowly, with half times of about a year.[8] Read more in what a calorie deficit is and how many calories to eat to lose weight.
When to talk to a clinician
References & further reading
- 1.A new predictive equation for resting energy expenditure in healthy individuals, American Journal of Clinical Nutrition (Mifflin et al.), 1990
- 2.Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review, Journal of the American Dietetic Association (Frankenfield et al.), 2005
- 3.Bias and accuracy of resting metabolic rate equations in non-obese and obese adults, Clinical Nutrition (Frankenfield), 2013
- 4.Dietary reference intakes for energy: factors affecting energy expenditure and requirements, National Academies of Sciences, Engineering, and Medicine, 2023
- 5.Dietary reference intakes for energy: summary, National Academies of Sciences, Engineering, and Medicine, 2023
- 6.Dietary reference intakes for energy: energy expenditure and physical activity level, National Academies of Sciences, Engineering, and Medicine, 2023
- 7.Human energy requirements: report of a joint FAO/WHO/UNU expert consultation, section 5, Food and Agriculture Organization of the United Nations, 2004
- 8.Quantification of the effect of energy imbalance on bodyweight, The Lancet (Hall et al.), 2011
- 9.Eating disorders, National Institute of Mental Health
- 10.Low blood glucose (hypoglycemia), NIDDK (NIH)
Eashan Vagish
Founder, Dalia Health
Eashan Vagish is the founder of Dalia Health, where he works on making heart and metabolic health easier to understand and track. He writes these guides to answer the health questions people actually ask, in plain language, with links to the research behind every claim.
Medical disclaimer: This article is for general educational purposes only and is not medical advice. It is not a substitute for diagnosis or treatment from a qualified healthcare professional. Always talk to your doctor about your individual health, and seek immediate care for any urgent symptoms.
How we write, source and correct these guides: our editorial policy. Spot an error? Email info@daliahealth.com.
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