What is the most accurate BMR formula?

The Mifflin-St Jeor equation (1990) is widely considered the most accurate for the general population. Katch-McArdle is more accurate if you know your lean body mass. Harris-Benedict (1919, revised 1984) is the classic formula.

How accurate is activity level multiplier?

Activity multipliers are rough estimates. Most people overestimate their activity level. If your weight is not changing as expected, try stepping down one activity level.

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BMR & TDEE Calculator

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Age (years)

Sex

Weight (kg)

Height

Activity Level

Body Fat % (optional - for Katch-McArdle)

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Calculate calories burned at rest (BMR) and daily needs (TDEE) using three formulas: Mifflin-St Jeor, Harris-Benedict, Katch-McArdle. Shows calorie goals for weight loss, maintenance, and gain.

How to Use

1Enter your age, sex, weight, and height - select metric or imperial
2Choose your activity level from the dropdown (sedentary to super active)
3Click Calculate to see BMR from all three formulas (Mifflin-St Jeor, Harris-Benedict, Katch-McArdle)
4TDEE = BMR × your activity multiplier - shown prominently
5Calorie goals for weight loss, maintenance, and gain are displayed with the calorie amounts

Features

3 formulas: Mifflin-St Jeor, Harris-Benedict, Katch-McArdle
Activity levels ×1.2 to ×1.9
TDEE with calorie goals for loss, maintenance, gain
All three BMR results shown for comparison
Metric and Imperial units
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BMR & TDEE Calculator

How to Use

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