Lean Body Mass Calculator (Boer Formula)
Estimate fat-free mass from height and weight.
Enter your values
Choose one of: Male, Female.
Enter the weight in kg.
Enter the height in cm.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Lean body mass
- 60.9 kg
- Estimated fat mass
- 19.1 kg
- Body fat %
- 23.9%
- Lean mass %
- 76.1%
Quick answer
Lean body mass is total weight minus estimated fat mass, calculated from the Boer formula.
Men: LBM = 0.407W + 0.267H - 19.2; Women: LBM = 0.252W + 0.473H - 48.3
At a glance
| What it does | Estimate fat-free mass from height and weight. |
|---|---|
| Category | Health |
| Inputs needed | Sex, Weight, Height |
| Main output | Lean body mass |
| Formula | Men: LBM = 0.407W + 0.267H - 19.2; Women: LBM = 0.252W + 0.473H - 48.3 |
| Cost | Free — no sign-up, no download |
How to use the Lean Body Mass Calculator (Boer Formula)
- 1Enter sex, weight and height.
- 2The Boer formula estimates fat-free mass from body size alone.
- 3This is an estimate — it does not measure your actual composition. For precise numbers use DEXA or hydrostatic weighing.
Inputs explained
- Sex
- Choose one of: Male, Female.
- Weight(kg)
- Enter the weight in kg.
- Height(cm)
- Enter the height in cm.
Worked example
Using the values the calculator loads with:
Inputs
- SexMale
- Weight80 kg
- Height178 cm
Results
- Lean body mass60.9 kg
- Estimated fat mass19.1 kg
- Body fat %23.9%
- Lean mass %76.1%
Frequently asked questions
Is Boer accurate?
It correlates well at a population level but can be off by a few kg for individuals with unusual builds.
Why does it matter?
Lean mass drives your resting calorie burn and protein needs more than total weight does.
What do I need to enter into the Lean Body Mass Calculator (Boer Formula)?
Just 3 values: sex, weight, height. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Lean Body Mass Calculator (Boer Formula) work out the answer?
Lean body mass is total weight minus estimated fat mass, calculated from the Boer formula. It applies the formula Men: LBM = 0.407W + 0.267H - 19.2; Women: LBM = 0.252W + 0.473H - 48.3 and shows the working so you can check each step by hand.
Is the Lean Body Mass Calculator (Boer Formula) free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.