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Module · Fitness · Metabolism
BMR Calculator
Estimate your Basal Metabolic Rate — the calories your body burns at rest — using Mifflin-St Jeor (or Katch-McArdle if you know your body-fat %).
About you
Your BMR
1,618
kcal / day at rest
Formula: Mifflin-St Jeor
TDEE by activity level
Sedentary × 1.21,941 kcal
Light exercise × 1.3752,224 kcal
Moderate exercise × 1.552,507 kcal
Very active × 1.7252,790 kcal
Extra active × 1.93,073 kcal
Katch-McArdle used when body-fat % is provided (0.0%).
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Guide
How BMR Calculator works
Step 01
Enter details
Sex, age, height, weight — optionally your body-fat % for a more accurate estimate.
Step 02
Formula auto-selects
Katch-McArdle is used if body-fat % is provided; otherwise Mifflin-St Jeor.
Step 03
See TDEE table
Total Daily Energy Expenditure across 5 activity multipliers so you can plan cutting or bulking.
FAQ
Frequently asked
What is BMR?+
The number of calories your body burns at complete rest — just to keep organs functioning. Multiply by an activity factor to get TDEE.
Mifflin-St Jeor vs Harris-Benedict?+
Mifflin-St Jeor is more accurate for modern populations. We use it by default.
When should I use Katch-McArdle?+
If you know your body-fat % (from DEXA, BIA scale, or our Body Fat Calculator), Katch-McArdle accounts for lean mass and is more accurate.