What is TDEE and how do I estimate mine?

Total daily energy expenditure (TDEE) is the calories your body uses in a day—mostly resting metabolism, daily movement, planned exercise, and digesting food. A common estimate multiplies Mifflin–St Jeor basal metabolic rate (BMR) by an activity factor; it is a planning number, not a lab test.

Key numbers

Mifflin–St Jeor BMR (men): 10 × kg + 6.25 × cm − 5 × age + 5; women use −161 instead of +5.^[1]
Activity factors often used with BMR: 1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 very active, 1.9 extra active.^[2]
TDEE parts (typical shares): BMR/REE about 60–70%, physical activity (NEAT + exercise) about 15–50%, TEF about 10%.^[3]
Build maintenance uses body weight (kg) × 30–35 kcal/day—not Mifflin–St Jeor. A quick sanity check is weight in kg × 30 kcal.(MFM methodology)
Validation reviews find Mifflin–St Jeor within about ±10% of measured expenditure for many adults—still an estimate.^[4]

TDEE = Total Daily Energy Expenditure

Example: a moderately active day

BMR 65% — energy at rest
NEAT 15% — everyday movement
EAT 10% — planned exercise
TEF 10% — digesting food

BMR 65%

NEAT 15%

EAT 10%

TEF 10%

Eating below TDEE
Weight often trends down
1,500 kcal example
Eating at TDEE
Weight stays about steady
2,000 kcal example
Eating above TDEE
Weight often trends up
2,500 kcal example

BMR/REE about 60–70%, physical activity (NEAT + exercise) about 15–50%, TEF about 10%. Source: NCBI NBK591031 (Dietary Reference Intakes for Energy).

Show data

Example: a moderately active day

BMR/REE about 60–70%, physical activity (NEAT + exercise) about 15–50%, TEF about 10%

TDEE parts on an example moderately active day
Component	Example share	Typical range	Example kcal	Notes
BMR — Basal Metabolic Rate	65%	about 60–70% (BMR/REE)	1,300	Basal or resting energy expenditure—the largest share of TDEE for most adults; varies with body size, age and lean mass.
NEAT — Non-Exercise Activity Thermogenesis	15%	physical activity (NEAT + exercise) about 15–50%	300	Non-exercise movement—posture, walking, chores and other daily activity outside planned workouts.
EAT — Exercise Activity Thermogenesis	10%	physical activity (NEAT + exercise) about 15–50%	200	Planned exercise and sport—the structured part of activity thermogenesis.
TEF — Thermic Effect of Food	10%	about 10%	200	Energy used to digest, absorb and store what you eat.

Source: NCBI Bookshelf — Dietary Reference Intakes for Energy (2023)

Intake vs example TDEE for TDEE = Total Daily Energy Expenditure
Scenario	kcal/day	vs example TDEE	Notes
Below TDEE	1,500	−500 kcal/day	A calorie deficit for gradual fat-loss planning. MFM Build’s “lose” goal uses this same 500 kcal offset from its maintenance estimate—not a guarantee of results.
At TDEE	2,000	0 kcal/day	Estimated maintenance—energy in roughly matches energy out. Build’s “maintain” goal keeps this offset at zero.
Above TDEE	2,500	+500 kcal/day	A surplus for weight gain or muscle-building phases. Build’s “gain” goal adds 500 kcal/day to its maintenance estimate.

What makes up TDEE?

TDEE is the sum of basal metabolic rate (BMR, energy at rest), non-exercise activity (NEAT), planned exercise (EAT), and the thermic effect of food (TEF). The stacked chart on this page shows typical shares on a moderately active example day.

When you eat about TDEE, weight tends to stay fairly stable. Eating below or above shifts energy balance over time—see the calorie deficit guide for how MFM plans a modest deficit.

Estimate TDEE with Mifflin–St Jeor

Enter weight, height, age, sex, and activity level in the calculator below. BMR comes from the Mifflin–St Jeor equation; multiply BMR by the activity factor to get an estimated TDEE in kcal/day.

For a fast check only, multiply body weight in kilograms by 30—that one-number shortcut ignores height, age, sex, and activity and can be off by several hundred kcal for some people. Macro Friendly Meals Build still uses its kg × 30–35 maintenance shortcut on purpose.

Does exercise change TDEE?

Yes. Planned workouts are part of exercise activity thermogenesis (EAT), and everyday movement is NEAT. Activity factors bundle both into one multiplier because hour-by-hour tracking is impractical for most people.

If your job or training load changes, pick a different activity level and re-estimate—do not treat one TDEE number as permanent.

Worked example

For an 80 kg (176 lb), 178 cm, 35-year-old man who is moderately active, Mifflin–St Jeor gives a BMR of 1742.5 kcal/day. Multiplying by the moderate activity factor (1.55) yields an estimated TDEE of 2700.9 kcal/day. The kg × 30 quick check for 80 kg is 2400 kcal/day—close for some people, but it ignores height, age, sex, and activity.

TDEE calculator (Mifflin–St Jeor)

Enter your stats for an estimated BMR and TDEE. Nothing is saved. Build on the home page still uses weight × 30–35 kcal for maintenance.

Weight

Height (cm)

Age (years)

Sex (for BMR equation)

Activity level

Estimated BMR: 1742.5 kcal/day
Estimated TDEE: 2700.9 kcal/day
Quick check (kg × 30): 2400 kcal/day

Formula: BMR × 1.55 (Moderately active). Rounded for display; your clinician may use different inputs.

Open Build Calorie deficit guide

How MFM uses this

Build Sets maintenance from body weight (kg × 30–35 kcal), then applies lose, maintain, or gain offsets. It does not use the Mifflin calculator on this page.
Calorie deficit guide Explains eating below TDEE, the 500 kcal planning shortcut, and the same TDEE diagram used here.
Macros Left See what fits after partial-day intake using Build’s weight-based maintenance estimate.
Learn hub More short guides on protein, macros, and how MFM estimates nutrition.

What we can't do (yet)

Mifflin–St Jeor and activity factors are population averages—not a metabolic lab test or medical prescription.
Build on MFM does not read this calculator; its maintenance math stays weight × 30–35 kcal.
Recipe and food kcal on the site are editorial estimates; logging error adds uncertainty.
Not for starting a very low-calorie diet without clinician supervision.

Questions

What is TDEE in plain terms?

TDEE is the total calories your body burns in a day from resting metabolism, movement, exercise, and digesting food. It is the maintenance side of the energy-balance equation.

What is the difference between BMR and TDEE?

BMR (basal metabolic rate) is energy at rest—breathing, organs, and temperature. TDEE adds NEAT, planned exercise, and TEF on top of BMR. Most adults’ BMR is the largest single share of TDEE.

How accurate are TDEE calculators?

Formula estimates often land within about ±10% of measured expenditure for many adults, but activity multipliers are guesses. Treat any number as a starting point and adjust with trends, hunger, and clinician advice.

Does exercise count toward TDEE?

Yes. Planned exercise is EAT; other daily movement is NEAT. Standard calculators combine them into one activity factor instead of counting every step.

What is the thermic effect of food (TEF)?

TEF is the energy used to digest, absorb, and store food—often roughly 10% of intake. It is a smaller slice than BMR for most people but still part of TDEE.

How do I use TDEE to lose weight?

Eat a modest amount below your estimated TDEE so energy intake is lower than expenditure over time. Macro Friendly Meals covers deficits, safety limits, and Build’s 500 kcal lose offset on the calorie deficit learn page.

General education, not medical advice. Nutrition values on MFM are estimates. For kidney disease, pregnancy or breastfeeding, work with a clinician on calorie and protein targets. If you have an eating-disorder history, skip DIY calorie math and talk to a doctor or registered dietitian; in the U.S., call or text 988 (Suicide & Crisis Lifeline) and the National Alliance for Eating Disorders helpline at 866-662-1235 (weekdays, Eastern time).

Try it

Open Build with MFM’s weight-based maintenance shortcut (kg × 30–35 kcal)—not the Mifflin calculator on this page.

Build maintenance estimate