The easiest way to calculate your body fat percentage is with your BMI (Body Mass Index). For people who don’t exercise, this is a great measure to determine whether someone is under or overweight, even though BMI is not always accurate. After all, if you do a lot of strength training, you have more muscle and are therefore automatically heavier. Those people are then overweight according to the Body Mass Index and should lose weight, while they have very little fat. Not very accurate. Yet researchers have found a strong relationship between BMI and fat percentage. And all you need is a scale and a tape measure!

You calculate your BMI by first measuring your weight. Then you measure your height, without shoes and socks. Now that you have both data, divide your weight by the square of your height. The formula looks like this: BMI = weight (kg) / (height (m2))^2. In other words, BMI = 70 / (1.75 * 1.75) = 22.86.


Another way to measure your BMI is with the skinfoldimeter. Take a piece of skin (including fat) and then place the skinfoldimeter on it. By then pinching it closed, you measure the thickness of this skinfold in millimeters. You then put these figures into the following formula to calculate your fat percentage:

Fat percentage (V%) = 0.29288 * (sum of skin folds in millimeters) – 0.0005 * (sum of skin folds in millimeters)^2 + 0.15845 * age – 5.76377

Body parts to be measured:

  • Chest:
    You measure the top of your chest at the level of your armpit. Measure at half the space between the armpit and the nipple. Grab a vertical fold. For women, grab the crease a little closer to the armpit.
  • Upper thigh:
    Grab a vertical skin fold on the thigh in the middle of the thigh.
  • Abdomen:
    Grab a vertical skin fold about 2-3 inches next to the navel.
  • Hip:
    For the hip, use a diagonal crease just above the hip bone.
  • Armpit:
    Measure a horizontal fold flush below the armpit.
  • Shoulder blade:
    Grab a diagonal crease on the inside of the back flush under either shoulder blade.
  • Tricep:
    Measure a vertical skin fold in the middle of the tricep.

The underwater measurement

The idea is to sit on a chair with tight swimwear on. You are then immersed in a bathtub and must blow all the air out of your lungs. Because of your difference in weight in and out of the water, an attempt is made to estimate your fat percentage.

This “gold standard” also uses mathematical models. For example, if you don’t blow all the air out of your lungs, or you still have an air bubble in your hair or in your intestines, that again is fodder for measurement error. You also can’t do this method everywhere, so it’s not as accessible. And it also has a measurement error of 5 to 6%.


While BMI is a simple measure of body weight, it can be inaccurate for people with a lot of muscle mass. Using a skinfoldimeter provides a detailed estimate of fat percentage, but requires accurate measurements and formulas. No method is perfect, so it is advisable to consider different indicators and professional assessments for a more complete picture of health.

If you have too much fat percentage, the Jake Light shakes are advisable to use. These contain fewer calories and help you limit your calorie intake. If you are just below BMI, then choose Jake Sports to increase your calorie intake. Are you looking for good support for a healthy lifestyle? Then choose Jake Original.

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