Basal Metabolic Rate is the number of calories your body burns at complete rest to sustain basic functions including breathing, circulation, cell repair, and temperature regulation. It represents the minimum energy your body needs just to stay alive and is typically the largest single component of your total daily energy expenditure, often accounting for 60 to 70 percent of total calorie burn.

Which BMR formula is most accurate?

Mifflin-St Jeor is the most widely validated formula for general adult populations and is commonly recommended by dietitians for planning. Katch-McArdle tends to fit better for people who know their body fat percentage because it calculates from lean mass directly rather than total body weight, making it more precise for lean or heavily muscled individuals where weight alone is a poor predictor.

Why is my TDEE an estimate?

Activity multipliers are averages drawn from population studies and cannot capture your individual physiology, workout intensity, or non-exercise movement patterns. A desk job with three weekly gym sessions may sit between two different activity labels. Track your weight for two to four weeks at a fixed calorie intake and adjust by 100 to 200 kcal up or down until your weight trends match your goal.

How do lose-weight calorie targets map to pounds per week?

A 500 kcal per day deficit below your TDEE is the commonly cited target for losing roughly one pound per week based on the 3,500 calorie per pound estimate. A 250 kcal per day deficit is associated with approximately half a pound per week. Actual results vary with water retention, sleep quality, training volume, and how accurately you track intake.

Should I use Harris-Benedict or Mifflin-St Jeor?

Both formulas are shown so you can see the range rather than rely on a single number. Most coaches and registered dietitians default to Mifflin-St Jeor because it has been validated more recently and tends to be more accurate for modern sedentary and moderately active adults. Use the result that aligns with your scale trend over several weeks rather than the highest figure.

TDEE Calculator for Daily Calorie Planning

Total daily energy expenditure is an estimate of the energy a person uses in a day, combining resting energy needs with activity. A TDEE estimate is a planning input, not a diagnosis or a guarantee of weight change.

Find your actual daily calorie burn before setting any goal.

Want just your BMR without an activity level? Use our BMR Calculator.

SexAge (years)

Unit system

Height (cm)Weight (kg)

Activity levelGoal

Body fat % (optional, for Katch-McArdle)

TDEE (Mifflin-St Jeor)

2,711 kcal

Activity: Moderately active (3–5 days/week)

Goal calories (Maintain)

2,611–2,811 kcal/day

-0.2 to +0.2 lb/week

BMR by equation

Mifflin-St Jeor

1,749 kcal

TDEE: 2,711 kcal

Harris-Benedict (revised)

1,830 kcal

TDEE: 2,836 kcal

Katch-McArdle

Enter body fat % to show lean-mass BMR.

TDEE by activity (MSJ BMR)

Level	Multiplier	TDEE
Sedentary	×1.2	2,099 kcal
Lightly active	×1.375	2,405 kcal
Moderately active	×1.55	2,711 kcal
Very active	×1.725	3,017 kcal
Extra active	×1.9	3,323 kcal

Directional macros (goal midpoint)

Protein 141 g
Carbs 368 g
Fat 75 g

Directional split at goal midpoint using 0.8 g protein per lb body weight (add body fat % for lean-mass protein).

BMR equations are estimates. Individual metabolism often varies by about 15–20%. Track weight for 2–4 weeks and adjust calories by 100–200 kcal if results drift. Not medical advice.

How to use a TDEE estimate

TDEE is an estimate of the total energy a person uses in a day, including resting metabolism and physical activity. A TDEE calculator provides a starting estimate; changes in body weight and energy needs vary between people.

What does total daily energy expenditure mean?

Total daily energy expenditure is the energy your body uses across a typical day. It includes energy needed for basic physiological functions at rest, movement and planned exercise, and the energy used to process food. A calculator combines the requested inputs with an equation and activity assumption to produce an estimate.

The estimate is not a diagnosis, metabolic test, or guarantee of a future result. Sleep, stress, illness, body composition, movement outside exercise, and measurement error can affect the relationship between an estimate and observed change.

How does this TDEE calculator estimate energy needs?

The calculator uses the inputs shown in its interface, including age, sex, height, weight, and activity level. It estimates resting energy needs, then applies an activity assumption to estimate a full-day total. The result depends on the method and values used.

Keep units consistent. Record the inputs and method when comparing results so you can identify what changed.

How do activity levels change the estimate?

Activity selections are broad categories, not direct measurements of every movement. Labels such as sedentary, moderate, and very active can mean different things to different people. A walking job may not fit the same category as a desk job with several weekly workouts.

Use the closest honest description of your usual week. If your schedule varies, calculate more than one plausible scenario and treat the range as a planning aid.

Why can your actual energy needs differ?

Formulas use population-based assumptions while individuals differ in body composition, movement, health, and routine. Scale readings can also change with water, glycogen, sodium, digestive contents, and timing.

Suppose a calculator returns 2,200 calories per day for one set of inputs. That figure is not a promise that eating exactly 2,200 calories will produce a fixed result. It is a reference point to compare with later observations under similar tracking conditions.

How should you use a TDEE estimate safely?

Use the output to organize questions and track patterns, not to replace medical care or individualized nutrition advice.

Record the date, inputs, activity assumption, and output.
Keep the measurement method reasonably consistent.
Review trends instead of reacting to one reading.
Ask a qualified professional when you need individual medical or nutrition advice.

Compare another formula-based reference with the OnSumo Ideal Weight Calculator. The OnSumo Cat Age Calculator is a separate example of a calculator that provides an estimate without replacing professional judgment.

For more detail on energy calculations, see the National Academies Dietary Reference Intakes and the NIH Body Weight Planner.

Frequently asked questions

What is BMR?
Basal Metabolic Rate is the number of calories your body burns at complete rest to sustain basic functions including breathing, circulation, cell repair, and temperature regulation. It represents the minimum energy your body needs just to stay alive and is typically the largest single component of your total daily energy expenditure, often accounting for 60 to 70 percent of total calorie burn.
Which BMR formula is most accurate?
Mifflin-St Jeor is the most widely validated formula for general adult populations and is commonly recommended by dietitians for planning. Katch-McArdle tends to fit better for people who know their body fat percentage because it calculates from lean mass directly rather than total body weight, making it more precise for lean or heavily muscled individuals where weight alone is a poor predictor.
Why is my TDEE an estimate?
Activity multipliers are averages drawn from population studies and cannot capture your individual physiology, workout intensity, or non-exercise movement patterns. A desk job with three weekly gym sessions may sit between two different activity labels. Track your weight for two to four weeks at a fixed calorie intake and adjust by 100 to 200 kcal up or down until your weight trends match your goal.
How do lose-weight calorie targets map to pounds per week?
A 500 kcal per day deficit below your TDEE is the commonly cited target for losing roughly one pound per week based on the 3,500 calorie per pound estimate. A 250 kcal per day deficit is associated with approximately half a pound per week. Actual results vary with water retention, sleep quality, training volume, and how accurately you track intake.
Should I use Harris-Benedict or Mifflin-St Jeor?
Both formulas are shown so you can see the range rather than rely on a single number. Most coaches and registered dietitians default to Mifflin-St Jeor because it has been validated more recently and tends to be more accurate for modern sedentary and moderately active adults. Use the result that aligns with your scale trend over several weeks rather than the highest figure.

Related tools

Turning TDEE into a plan

For slow fat loss, many people eat 300 to 500 calories under TDEE. That's roughly a third to half a kilogram a week at the start. Bigger cuts bring faster loss and also more hunger, lost muscle and a harder time sticking with it.

To gain muscle, add 200 to 300 calories and lift weights. Faster than that and most of the extra turns into fat.

Protein matters in both cases. A common range is 1.4 to 2 grams per kilogram of body weight for people who train. The macro calculator on this site can split your target into protein, carbs and fat.

A quick example

A 35 year old man, 178 cm and 82 kg, has a BMR near 1,760 calories using the Mifflin-St Jeor equation. With an activity factor of 1.375, his TDEE is about 2,420. To lose slowly he might eat near 2,000 to 2,100. After three weeks, if the scale hasn't moved, he'd trim another 150 or check that his weekend meals aren't undoing the week.