How to Calculate BMR: Formula, Meaning, and Examples
Learn how to calculate BMR with common formulas, what basal metabolic rate means, and how BMR fits into calories, TDEE, and maintenance.
Searching how to calculate BMR means you want your basal metabolic rate, the calories your body uses at rest just to maintain basic functions like breathing, circulation, and temperature regulation.
BMR Formula
One common formula is the Mifflin-St Jeor equation:
| Person | Formula |
|---|---|
| Men | BMR = 10W + 6.25H - 5A + 5 |
| Women | BMR = 10W + 6.25H - 5A - 161 |
W = weight in kilograms
H = height in centimeters
A = age in years
Example
A 30-year-old man weighs 80 kg and is 180 cm tall.
BMR = 10(80) + 6.25(180) - 5(30) + 5
BMR = 800 + 1,125 - 150 + 5
BMR = 1,780 calories/day
BMR vs TDEE
BMR is not the same as daily calorie needs. It is just the base. To estimate maintenance calories, you multiply BMR by an activity factor. That larger number is usually called TDEE, or total daily energy expenditure.
Why BMR Matters
BMR helps with:
- Estimating maintenance calories
- Planning fat loss or weight gain
- Comparing calorie needs over time
- Understanding energy needs at rest
The Bottom Line
To calculate BMR, use your age, sex, height, and weight in a formula such as Mifflin-St Jeor. Then use BMR as the starting point for TDEE and daily calorie planning.
Use the TDEE Calculator to estimate both BMR and maintenance calories together.
Informational note: BMR formulas are estimates. Medical conditions, body composition, and medications can change actual energy needs.
How to Calculate: Step-by-Step Guide
Gather your stats
Use your age, sex, weight, and height.
Apply a BMR formula
A common formula is Mifflin-St Jeor.
Use BMR as a base
Multiply BMR by an activity factor to estimate TDEE.