Some rely on their gut feeling, others on the display of their scales. Still others swear by a measuring tape that they put around their waist. As different as all these measuring methods are, they have one thing in common: they are quite vague. After all, there are many factors that determine what weight is good for your health. It can also be more precise.

Calculate ideal weight – this is how it works

BMI, the formula for the ideal weight

The Body Mass Index, BMI for short, is the most common ideal weight calculator of our time. You determine it by comparing your body weight in kilograms with your height in meters to the square. And so the whole thing looks like a formula:

body mass index = body weight : (height)²

An example: A man with a height of 1.85 metres weighs around 80 kilograms. Does he have his ideal weight? Let's let the BMI calculator decide.

man's body mass index = 80 : (1,85)²

Everything in the green area: With a BMI value of 23.37 the man moves in the weight class 18.5 to 24.9. He is of normal weight.

Calculating the ideal weight – a look at the BMI table

The first step is done: Your BMI value is set. To calculate your ideal weight, however, it takes more than juggling numbers. Just as important as the formula is the BMI table. And it has two messages for you: your weight class and your risk for weight-related secondary diseases.

Weight classBMI female*BMI male*Risk of sequelae
Underweight< 19< 20low
Normal weight19-2420-25on average
Overweight25-3026-30slightly Increased
Obesity31-4031-40high
severe obesity> 40> 40very high
*using the example of a 19-year-old person

What is my ideal weight? The thing with age

The ideal weight calculator takes age into account as well as weight and height. But why is that so important?

The ideal weight doesn't stay the same all your life. With age it shifts. Depending upon stage of life a few kilos more or less count as healthy. A larger upheaval begins from about 40 years; in these life years the metabolism often changes. You put on fat pads and gain weight naturally without suffering from obesity. The result: your normal weight shifts and with it the recommended BMI.

But the opposite can also happen. It is not uncommon for you to lose muscle mass as you get older, which in itself is significantly more than fat. Your body weight will then be correspondingly lower. It can even indicate underweight, although you do not run the risk of losing weight.

If you want to calculate your ideal weight, you should also take a look at this table:

AgeIdeal BMI margin femaleIdeal BMI margin male
19-2419-2421-26
25-3420-2522-27
35-4421-2623-28
45-5422-2723-28
55-6423-2824-29
> 6425-3025-30

The birth of the ideal weight calculator

The Belgian mathematician Adolphe Quetelet is regarded as the inventor of the body mass index. In the 1840s he was interested in human weight from a statistical point of view. After numerous studies, he came to a groundbreaking conclusion: the weight of a healthy person is approximately proportional to the square of his body length. In other words, a 20 percent taller person weighs up to 44 percent more.

That's how you get to a healthy level

According to the BMI calculator, you will reach your ideal weight? Congratulations, you are on the right track! Nevertheless, you should not just rely on it. After all, your body weight is dynamic and depends above all on your living and eating habits. Therefore you have to care for it. And so you take care of it:


  • calculate ideal weight regularly
  • drink a lot (at least 1.5 liters per day)
  • be active (at least one hour of sports per week)
  • balanced nutrition
  • only now and then sweet snacks
  • meaningful meal-eating breaks rhythm
By the way: If you want to keep your weight for a long time, you should know your gut well. After all, it plays a major role in fat burning. You get close to your digestive tract with the INTEST.pro from BIOMES. According to the latest biotechnological standard1 the team of experts analyses your intestinal flora. This way you can find out what your digestion is like. In order to support this through nutrition, you will receive a individual nutrition plan.

1. Cho I, Blaser M J. The human microbiome: at the interface of health and disease. Nature Reviews Genetics 2012:13, 260-270. https://www.nature.com/articles/nrg3182