Nutrition
How To Calculate TDEE
Total daily energy expenditure is the number of calories you burn in a day, made up of your resting metabolic rate plus everything else you do. Estimating it starts with the Mifflin-St Jeor equation for the resting rate, then scales that figure by an activity factor.
Quick Answer
TDEE = BMR x activity factor, BMR = 10w + 6.25h - 5a + s
- w
- Body weight in kilograms
- h
- Height in centimetres
- a
- Age in years
- s
- Plus 5 for men, minus 161 for women
A 35-year-old man weighing 80 kilograms at 180 centimetres has a resting rate of about 1,755 calories. At a moderate activity level that becomes a maintenance intake of roughly 2,720 calories a day.
What Is TDEE?
Total daily energy expenditure is the total number of calories a body burns in a day. It is the sum of the resting metabolic rate, the energy used to digest food, and the energy spent on movement and exercise.
The resting metabolic rate dominates. For most people it accounts for sixty to seventy percent of daily expenditure, which is why an estimate of it is the starting point for any calorie target.
The Mifflin-St Jeor equation is the most widely used estimate of the resting rate. It takes weight in kilograms, height in centimetres and age in years, and adds a constant that differs by sex: plus five for men and minus one hundred and sixty-one for women.
The equation is a regression fitted to measured data, not a law of nature. It is accurate to within about ten percent for most people, and it systematically overestimates for the very obese and underestimates for the very muscular.
The activity factor scales the resting rate up to total daily expenditure. A sedentary desk worker sits near one point two, light activity is about one point three seven five, moderate is one point five five, and hard daily training pushes past one point seven.
Choosing the activity factor honestly matters more than the equation itself. Most people overestimate their activity level, and a single step up the ladder adds several hundred calories a day to the target.
A deficit of about five hundred calories a day is the conventional target for losing roughly half a kilogram, or one pound, a week, since a pound of fat stores about three thousand five hundred calories.
A surplus of about five hundred calories a day supports steady weight gain and muscle growth when paired with resistance training. Larger surpluses tend to add fat rather than accelerate muscle gain.
The targets should never fall below a sensible floor. Intakes under about twelve hundred calories a day are difficult to sustain and risk nutrient shortfalls, which is why the calculator clamps the aggressive target rather than letting it run down.
As weight changes, the resting rate changes with it. A person who loses ten kilograms needs fewer calories for the same activity, which is why weight loss slows over time even when the diet does not change.
Tracking actual intake for a week and comparing it with the estimated maintenance figure is the fastest way to calibrate. If weight is stable, the true maintenance is whatever is being eaten.
The estimate ignores medical conditions, medication, body composition and sleep, all of which shift expenditure. It is a starting point to be adjusted against real results, not a fixed prescription.
Anyone managing a medical condition, an eating disorder or a pregnancy should treat the number as informational and work with a clinician rather than a calculator.
Formula
BMR = 10w + 6.25h - 5a + s
The resting metabolic rate in calories per day, with s equal to plus five for men and minus one hundred and sixty-one for women.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| w | Weight | kg | Body weight in kilograms. |
| h | Height | cm | Height in centimetres. |
| a | Age | years | Age in years. |
| s | Sex constant | calories | Plus 5 for men, minus 161 for women. |
TDEE = BMR x activity factor
The resting rate scaled by an activity factor that reflects how much the person moves.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| BMR | Resting rate | calories | Calories burned at complete rest. |
| A | Activity factor | factor | From 1.2 for sedentary to 1.9 for extra active. |
How To Calculate TDEE
- 1
Convert the inputs
Use kilograms for weight and centimetres for height. Divide pounds by 2.205 and multiply inches by 2.54 to convert.
- 2
Compute the resting rate
Multiply weight by ten, height by six point two five and age by five, then add the sex constant.
- 3
Pick an honest activity factor
Sedentary 1.2, light 1.375, moderate 1.55, very active 1.725, extra active 1.9. Most desk workers belong at 1.2 or 1.375.
- 4
Scale to maintenance
Multiply the resting rate by the activity factor. The result is the estimated daily maintenance intake.
- 5
Set a target
Subtract five hundred calories for steady loss, one thousand for faster loss, or add five hundred for a surplus.
Examples
Example 1: Male, 35, 80 kg, 180 cm, moderately active
- Sex
- Male
- Age
- 35
- Weight (kg)
- 80
- Height (cm)
- 180
- Activity level
- Moderate (exercise 3-5 days a week)
| Step | Calculation | Result |
|---|---|---|
| Resting rate | 10 x 80 + 6.25 x 180 - 5 x 35 + 5 | 1755.00 |
| Activity factor | 1.55 | 1.55 |
| Maintenance | 1755.00 x 1.55 | 2720.25 |
| Mild deficit | 2720.25 - 500 | 2220.25 |
| Aggressive deficit | 2720.25 - 1000 | 1720.25 |
| Surplus | 2720.25 + 500 | 3220.25 |
Result: Maintenance is 2,720.25 calories a day, from a resting rate of 1,755.00 scaled by 1.55. A mild deficit target is 2,220.25, an aggressive one 1,720.25, and a surplus 3,220.25.
Example 2: Female, 35, 90 kg, 180 cm, moderately active
- Sex
- Female
- Age
- 35
- Weight (kg)
- 90
- Height (cm)
- 180
- Activity level
- Moderate (exercise 3-5 days a week)
| Step | Calculation | Result |
|---|---|---|
| Resting rate | 10 x 90 + 6.25 x 180 - 5 x 35 - 161 | 1689.00 |
| Activity factor | 1.55 | 1.55 |
| Maintenance | 1689.00 x 1.55 | 2617.95 |
| Mild deficit | 2617.95 - 500 | 2117.95 |
| Aggressive deficit | 2617.95 - 1000 | 1617.95 |
| Surplus | 2617.95 + 500 | 3117.95 |
Result: Maintenance is 2,617.95 calories a day, from a resting rate of 1,689.00. The targets are 2,117.95 for a mild deficit, 1,617.95 for an aggressive one, and 3,117.95 for a surplus.
Calculator
Maintenance calories (TDEE)
2,720.25
- Resting rate (BMR)
- 1,755
- Mild deficit target
- 2,220.25
- Aggressive deficit target
- 1,720.25
- Surplus target
- 3,220.25
Values update as you type. This calculator covers the single scenario its formula assumes — see Common Mistakes for what it leaves out.
Prefer a full-width tool? Open the TDEE calculator page.
Common Mistakes
Overstating the activity factor
Most people pick the level they aspire to rather than the one they live. A single step too high adds several hundred calories a day and quietly stops weight loss.
Mixing pounds and kilograms
The equation expects kilograms and centimetres. Entering pounds as kilograms inflates the resting rate by more than a factor of two.
Treating the estimate as exact
The equation is accurate to roughly ten percent for most people and worse at the extremes. Compare the estimate against a week of real intake before trusting it.
Forgetting the sex constant
The constant is plus five for men and minus one hundred and sixty-one for women, a difference of one hundred and sixty-six calories. Using the wrong one shifts every target.
Cutting calories too hard
A deficit of more than about a thousand calories a day is hard to sustain and risks losing muscle and micronutrients. Slower loss is more durable.
Ignoring that the resting rate falls with weight
As weight drops the resting rate drops too, so a target that worked at the start will eventually become maintenance. Recalculate after every few kilograms.
Leaving out exercise calories twice
The activity factor already includes training. Adding logged workout calories on top of a moderate multiplier counts the same effort twice.
FAQ
What is the difference between BMR and TDEE?
The resting rate is what the body burns at complete rest. Total daily energy expenditure is the resting rate scaled up by an activity factor, so it includes movement, exercise and digestion.
Which equation does the calculator use?
The Mifflin-St Jeor equation, which is the most accurate of the simple predictive equations for most adults and is the one recommended by the Academy of Nutrition and Dietetics.
How many calories should I eat to lose a pound a week?
About five hundred fewer than maintenance each day, since a pound of fat stores roughly three thousand five hundred calories. The calculator shows that target as the mild deficit figure.
Why does the aggressive target stop at 1,200 calories?
Intakes below about twelve hundred calories a day are difficult to sustain and risk nutrient shortfalls, so the calculator clamps the aggressive target rather than letting it fall further.
Does the estimate work for athletes?
It tends to underestimate for very muscular people, because muscle burns more at rest than the equation assumes. Athletes usually calibrate against tracked intake and weight change instead.
How often should I recalculate?
After every few kilograms of weight change, and whenever activity levels change. The resting rate moves with body weight, so the target moves with it.
References
- [1]The American Journal of Clinical Nutrition, A new predictive equation for resting energy expenditure in healthy individuals — https://pubmed.ncbi.nlm.nih.gov/2305711/
- [2]National Institute of Diabetes and Digestive and Kidney Diseases, Body Weight Planner — https://www.niddk.nih.gov/bwp
- [3]Academy of Nutrition and Dietetics, Adult Energy Needs and Estimating Calorie Requirements — https://www.eatright.org/