Lean Body Mass Calculator

Estimate your lean body mass (everything except fat) with the Boer, James and Hume formulas.

InstantPrivate — runs in your browserFree, no sign-up

Result

How to use

1
Choose your sex.
2
Enter your height and weight.
3
Compare lean body mass from three standard formulas and the body fat they imply.

Questions

What is lean body mass?

Lean body mass (LBM) is your total weight minus body fat — muscles, bones, organs, skin and water. It is used for some drug doses, protein targets and tracking fitness progress.

Which formula is used?

Boer (1984) is shown as the main result. Men: 0.407 × weight + 0.267 × height − 19.2. Women: 0.252 × weight + 0.473 × height − 48.3 (weight in kg, height in cm). James (1976) and Hume (1966) are shown for comparison.

Are these accurate for everyone?

They are estimates for adults based on height and weight only. For very muscular or very overweight people they can be off by several kilos. A DEXA scan or body composition analysis is more accurate.

About this Lean Body Mass tool

Lean Body Mass Calculator — Estimate your lean body mass (everything except fat) with the Boer, James and Hume formulas. It is one of 200 free tools on namasivayam.in, made by software engineer Namasivayam Vadivelan for everyday use in India.

Everything is calculated instantly in your browser: nothing you type or upload is sent to any server, there is no sign-up, and it works on mobile and desktop. Choose your sex.

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