Why use lean mass instead of total weight?

Muscle burns more calories at rest than fat does, so basing BMR on lean mass gives a more personalized estimate, particularly for people who are more muscular or leaner than average.

How do I know my body fat percentage?

Use a body fat calculator, skinfold calipers, a smart scale, or a DEXA scan. If you're unsure, the Mifflin-St Jeor or standard BMR calculators work from just height, weight, and age instead.

Katch-McArdle BMR Calculator

The Katch-McArdle formula estimates Basal Metabolic Rate (BMR) using lean body mass instead of total weight, making it more accurate for people who know their body fat percentage, especially athletic or leaner individuals.

Inputs

Results

BMR (Katch-McArdle): 1,839 kcal/day
Lean Body Mass: 68 kg

Try an example

Formula

BMR = 370 + 21.6 × Lean Body Mass (kg)

Learn How This Works

Metabolic Rate and Daily Nutrient Tracking

Katch-McArdle BMR, calcium, iron, and vitamin D daily values, and protein per meal — five calculations for tracking metabolism and micronutrient targets.

Frequently Asked Questions

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