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BMR Calculator

The Mifflin-St Jeor equation estimates basal metabolic rate from weight, height, age and sex. It fits modern populations better than the older Harris-Benedict formula.

Your numbers

BMR

1,568kcal

TDEE

2,430kcal

Formula

BMR = 10×Weight (kg) + 6.25×Height (cm) − 5×Age + 5 (M) / −161 (F)

The second figure assumes moderate activity (factor 1.55) — adjust activity in the TDEE calculator.

What to enter

InputDefaultAccepted range
Sex (M1 / F0)Where the formula splits by sex — enter 1 for male, 0 for female.10 ~ 1
AgeAge in completed years — it shifts by one depending on the birthday.301 ~ 120
Height (cm)Height in centimetres; converted to metres inside the formula.170100 ~ 250
Weight (kg)The second weight you are comparing against.6510 ~ 300

Step by step

FormulaBMR = 10×Weight (kg) + 6.25×Height (cm) − 5×Age + 5 (M) / −161 (F)
With the default numbersBMR = 10×65 + 6.25×170 − 5×30 + 5 (M) / −161 (F)
AnswerBMR = 1,568 kcal

Quick reference table

Results when only Age changes and everything else stays put.

AgeBMR (kcal)TDEE (kcal)
151,6432,546
22.51,6052,488
301,5682,430
451,4932,313
601,4182,197

What each result means

ResultAt default values
BMR (kcal)The calories you burn in a day doing nothing at all.1,568
TDEE (kcal)Daily calories burned once activity is included.2,430

Common mistakes

The second figure assumes moderate activity (factor 1.55) — adjust activity in the TDEE calculator.

Glossary

Sex (M1 / F0)
Where the formula splits by sex — enter 1 for male, 0 for female.
Age
Age in completed years — it shifts by one depending on the birthday.
Height (cm)
Height in centimetres; converted to metres inside the formula.
Weight (kg)
The second weight you are comparing against.
BMR
The calories you burn in a day doing nothing at all.
TDEE
Daily calories burned once activity is included.

Frequently asked questions

Q. How is BMR Calculator calculated?

BMR = 10×Weight (kg) + 6.25×Height (cm) − 5×Age + 5 (M) / −161 (F) — The Mifflin-St Jeor equation estimates basal metabolic rate from weight, height, age and sex. It fits modern populations better than the older Harris-Benedict formula.

Q. Can you walk through an example?

With Sex (M1 / F0) 1, Age 30, Height (cm) 170, Weight (kg) 65, the answer is BMR 1,568kcal.

Q. What do I need to enter?

Enter Sex (M1 / F0), Age, Height (cm), Weight (kg). The result recalculates as you type, and an empty box counts as zero.

Q. How much does the answer move if I change a number?

Changing only Age moves the answer to Age 15 → BMR (kcal) 1,643 and Age 60 → BMR (kcal) 1,418. The table below lays out five steps.

Q. How are the numbers rounded?

Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.

Q. Anything to watch out for?

The second figure assumes moderate activity (factor 1.55) — adjust activity in the TDEE calculator.

Related calculators

These calculators help you understand health figures; they do not replace diagnosis or prescription. See a clinician if you have symptoms.