Fat Mass by Skinfold Durnin and Womersley Calculator

Skinfold measurements:

Skinfold landmarks: [Open] - [Close]

Fat Mass :  %

What is fat mass? How to measure it?

Measuring fat mass is both very simple to do and highly prone to error. It is not uncommon, depending on the method of measurement, to have quite significant differences. It's normal, each modification of the place where the skinfold is measured, each change of moment during the day can generate different results.

Thus, what really matters is not the magic number, but the direction of the measurement (are the results up or down, are the changes fast or on the contrary slow), because anyway, the measurement will always be imprecise. But to have a global vision, several factors must be taken into account.

How to measure your fat mass?

The methods for measuring body fat are numerous and more or less precise. Measurements from the hand, various and varied skin folds with different calculation formulas, measurement of circumferences, etc.

You can quickly get lost. Especially if you are a zapper (and therefore change your methods according to the latest articles published on the Internet).

But do not forget one thing: even if it can be useful to follow its evolution, the simplest thing is still to look in the mirror and to weigh yourself. These two data are largely sufficient.

The skinfold method

This is the easiest and fastest method.

It is easy to understand, and inexpensive (a few tens of euros for the acquisition of pliers of the correct quality). The most difficult thing is not to make a mistake in the location of the skin folds to use: a few centimeters of error and your results will be wrong (all the more so if you are not exactly in the same place for each measurement).

In general, to be certain of the result, ask a professional to take the measurements (each time the same professional). Indeed, some areas can be complicated to measure alone (to reach it, take the measurement and at the same time read it).

But hey, you can perfectly ask your spouse to perform the measurement if he is sufficiently precise: do not forget that the measurement will never be 100% precise anyway. But do you need to know your body fat percentage to the nearest 0.05%?

After having taken the measurements as they should, it will be necessary to apply a method of calculation (each method requires measurements at specific places).

Depending on the desired precision, different methods will be used (more or less precise, but more or less complicated to operate).

Durnin Womersley's Formula

It is rather used for people with a very high-fat mass rate. We then use 4 skinfolds (biceps, triceps, subscapular, supra-iliac).

For men or women: % fat = (495 / (C – (M x log(sum of 4 skin folds)))) – 450

The values of C and M for women are as follows:

- from 17 to 19 years old C=1.1549 and M=0.0678

- from 20 to 29 years old C=1.1599 and M=0.0717

- from 30 to 39 years old C=1.1423 and M=0.0632

- from 40 to 49 years old C=1.1333 and M=0.0612

- over 50 years old C=1.1339 and M=0.0645

The values of C and M for humans are as follows:

- from 17 to 19 years old C=1.1620 and M=0.0678

- from 20 to 29 years old C=1.1631 and M=0.0632

- from 30 to 39 years old C=1.1422 and M=0.0544

- from 40 to 49 years old C=1.1620 and M=0.0700

- over 50 years old C=1.1715 and M=0.0779