Technical Calculator

Lean Body Mass Calculator

Enter the required inputs into the calculator and calculate the precise lean body mass of a person in seconds.

Use the lean Body Mass calculator to calculate the estimated LBM, also known as lean body weight (LBW) and body fat percentage The LBM calculator allows you to compare the results of various formulas such as Boer, the James, the Hume, and the Peters equations. It is a useful tool for tracking your fitness and health progress.

What Is Lean Body Mass (LBM)?

 LBM is the weight of your body after deducting the weight of your total body fat.  In other words, it’s the weight of muscles, your bones, other internal organs, and limbs without fat. Now you might have an idea of what is important in your mission of improving fitness and weight loss. When individuals talk about gaining muscle by consuming more protein or muscle-building workouts, what they are really discussing about gaining or building their skeletal muscle mass. The human body can actively grow and develop the skeletal muscle mass through proper exercise and nutrition.

Lean Body Mass Chart:

In the following LBM chart, we have provided the normal, high, and very high values of LBM for males and females. Let's have a look:

Gender Age Low(-) Normal(0) High(+) Very High(++)
Female 18-39 <24.3 24.3 - 30.3 30.4 - 35.3 ≥35.4
40-59 <24.1 24.1 - 30.1 30.2 - 35.1 ≥35.2
60-8 <23.9 23.9 - 29.9 30.3 - 34.9 ≥35.0
Male 18-39 <33.3 33.3 - 39.3 39.4 - 44.0 ≥44.1
40-59 <33.1 33.1 - 39.1 39.2 - 43.8 ≥43.9
60-8 <32.9 32.9 - 38.9 39.0 - 43.6 ≥43.7

Lean Body Mass Formula:

If you calculate how much lean body mass and body fat you have, you can plan your diet and workout accordingly to improve your body mass and reduce the fat. Lets take a look at the following formula:

LBM = BW - BF

Where;

The LBM formula’s that are taken into account for calculating LBM are as follows:

The Boer Formula:

For Men: 0.407 × weight[kg] + 0.267 × height[cm] - 19.2

For Women: 0.252 × weight[kg] + 0.473 × height[cm] - 48.3

The James Formula:

For Men: 1.1 × weight[kg] - 128 × ( weight[kg] / height[cm] ) 2

For Women: 1.07 × weight[kg] - 148 × ( weight[kg] / height[cm] ) 2

The Hume Formula:

For Men: 0.32810 × weight[kg] + 0.33929 × height[cm] - 29.5336

For Women: 0.29569 × weight[kg] + 0.41813 × height[cm] - 43.2933

Formula For Kids( The Peters Formula):

The Peters equation is used to calculate LBM of children (up to 13-14 years old) and this equation is based on an estimated extracellular volume (eECV) as given:

\(\ eECV\ =\ 0.0215\ .\ W^{0.6469}\ .\ H^{0.7236}\) eLBM = 3.8·eECV

How To Calculate Lean Body Mass?

Calculating lean body mass LBM becomes easy with the above lean muscle calculator, but remember that LBM is different for different genders because the body structure and requirements are different for males and females. Normally, females need to have more body fat than males so their mass will be lower than males. There are various body mass equations as we have discussed above but if you know your body fat percentage, then follow the below-mentioned steps:

  • First, you have to measure your total body weight
  • Then, you have to multiply your weight by the fat percentage
  • Right after, there is a need to subtract the result from your body weight as we have done in the following example

Practical Example:

Suppose you have the following inputs:
  • Total Body Weight = 160 pounds
  • Body Fat Percentage = 20%

Find the LBM?

Solution:

Fat Mass=160 pounds×(20/100) = 32 pounds

LBM =160 pounds−32 pounds = 128 pounds

Lean Body Mass Vs. Fat Free Mass:

Sometimes lean body mass and fat free mass are used in the same context but they are not. These two terms are not the same. The lean  mass includes the mass of, bones, muscles, water, ligaments, and tendon-internal organs On the other hand, fat free mass is calculated by subtracting all fat mass including essential fat from total mass. 

FAQ’s:

What Is A Good Lean Body Mass?

The good mass ranges from 70% to 90 %. The women tend to be near the lower end and the men near the higher end of the range.  Also, you can try the smart BMI calculator to calculate body mass index (BMI) for men, women, teens, and children, this tool shows you the precise measurements related to BMI.

What Is My Maximum Lean Body Mass?

To calculate maximum mass LBM, stick to the given formula:

Maximum mass LBM = (Your Height in Inches – 70) x 5 + 160

Why Is Lean Body Mass Important?

See the following points to understand its importance:

  • LBM is very important as it contributes to looking great or being stronger
  • Helps to assess progress towards fitness
  • Indicates the overall body composition and your health condition