Transparent method
The formula
Worked example
Example inputs
How to interpret the result
BMR estimates the energy your body burns doing nothing at all, no walking, no digesting a meal, just staying alive at rest, which makes it the floor a real daily calorie need gets built on top of, never the number itself to eat against. Treating BMR as a daily calorie target means eating for a person lying in bed all day, not the person actually living that day.
Before you rely on it
What to check
Add an activity multiplier on top of BMR before using the result as a daily target. TDEE, not BMR, is the number that reflects an actual day.
The common error
Where people go wrong with BMR calculator
Using BMR directly as a calorie goal. It measures resting energy use only, and eating at that level while doing any normal daily activity creates a larger deficit than intended.
Sensitivity evidence
How weight changes the basal metabolic rate
| Weight | Basal metabolic rate | BMR per pound of body weight |
|---|---|---|
| 136 | 1,542.3 | 11.3 |
| 153 | 1,619.4 | 10.6 |
| 170worked example | 1,696.5 | 10 |
| 187 | 1,773.6 | 9.5 |
| 204 | 1,850.7 | 9.1 |
Every input, tested
Which input moves the basal metabolic rate most
| Input | Tested from | To | Basal metabolic rate at each end | Swing |
|---|---|---|---|---|
| Height | 62 | 76 | 1,585.4 to 1,807.6 | 222.3 (13%) |
| Sex | Male | Female | 1,696.5 to 1,530.5 | 166 (9.8%) |
| Weight | 153 | 187 | 1,619.4 to 1,773.6 | 154.2 (9.1%) |
| Age | 26.0 years | 44.0 years | 1,741.5 to 1,651.5 | 90 (5.3%) |
Two variables at once
Basal metabolic rate by weight and height
| Weight \ Height | 55 | 69 | 83 |
|---|---|---|---|
| 136 | 1,320 | 1,542.3 | 1,764.5 |
| 153 | 1,397.1 | 1,619.4 | 1,841.6 |
| 170 | 1,474.2 | 1,696.5 | 1,918.7 |
| 187 | 1,551.3 | 1,773.6 | 1,995.8 |
| 204 | 1,628.5 | 1,850.7 | 2,073 |
Step by step
The worked example, input by input
| Input | Value used | What it means |
|---|---|---|
| Sex | Male | The Mifflin-St Jeor formula uses a different constant by sex. |
| Weight | 170 | Body weight in pounds. |
| Height | 69 | Height in inches. |
| Age | 35.0 years | Age in years. |
| Basal metabolic rate | 1,696.5 | |
| BMR per pound of body weight | 10 | |
Inputs, definitions and assumptions
Sex
The Mifflin-St Jeor formula uses a different constant by sex.
Weight
Body weight in pounds.
Height
Height in inches.
Age
Age in years.
Where the inputs come from
Enter your sex, weight, height and age. The Mifflin-St Jeor equation, found in studies to be one of the more accurate for healthy adults, is 10 times weight in kilograms plus 6.25 times height in centimeters minus 5 times age, plus 5 for men or minus 161 for women. The tool converts pounds and inches. Use your current weight, and note that the formula does not know your muscle mass, which raises real metabolic rate.
When the result stops applying
Predictions can be off by 10% or more for an individual because muscle, genetics, hormones and thyroid function vary. Weight loss lowers BMR as the body gets smaller and may reduce it further through adaptation. The formula is for adults and does not apply in pregnancy or certain illnesses. Metabolic rate declines gradually with age.
What to compare it with
Turn BMR into daily energy needs on the TDEE calculator, and plan intake on the calorie goal and macronutrient pages. The lean body mass and body fat calculators show composition, and the calories burned page adds exercise. A registered dietitian can tailor advice.
People also ask
Frequently asked questions
What is the difference between BMR and TDEE?
BMR is calories burned at rest, and TDEE adds the energy used for daily activity and exercise, so TDEE is the number that determines weight change.
Does muscle raise BMR?
Yes, somewhat. Muscle tissue burns more energy at rest than fat, so more lean mass raises BMR by a modest amount.
Is a BMR estimate accurate?
It is a good estimate for the average person, but individuals vary by around 10% or more, so use it as a starting point and adjust to your results.