Body measurement indexes

Body mass indexes (BMI) are measures of body weight distribution and are used to assess whether or not a person is at a healthy weight.

Body Index Calculator

The calculator calculates the following body mass indices: BMI, BSI, Ponderal and Broca indices, WHR, WHtR, body fat and FFMI.

Basic data entry:


Body Mass Index BMI

Body mass index (BMI) is a measure that relates weight to the square of height. BMI is an approximate guide because it does not take into account stature or weight distribution. Since the early 1980s, BMI has also been used by the World Health Organization. The interpretation of the calculated BMI value is done by comparison with the tabulated average values of the population. This means that the normal range corresponds to the average of the population at the time of the survey.

Waist measurement:

Find the top of your hip bone and the bottom of your ribs. Exhale normally. Place the tape measure halfway between these points and wrap it around your waist.

Entering the waist size:

Waist size

Body Shape Index (BSI or ABSI)

The Body Shape Index (BSI) or more precisely the A Body Shape Index (ABSI) can be considered as a refinement of the Body Mass Index (BMI). The ABSI differs essentially from the BMI by taking into account the waist circumference in addition to the weight and height. The calculated ABSI gives us information about the distribution of the body shape. The higher the ABSI, the greater the proportion of abdominal fat in relation to other parts of the body such as muscle or subcutaneous fat in the arms, legs or torso.

Risk classification

Ponderal index

The Ponderal index, also known as the Rohrer index, is a measure of body weight (physically correct, body mass) relative to height, similar to the body mass index. But unlike the latter, the mass m is divided by the power of 3 of the height l, i.e. it is related to a (fictitious) volume rather than to an area.

Broca index

Broca index is a measure to calculate a person's normal weight. Broca's Index is only a rough estimate and is best applied to the average height range; for very tall and very short people, the BMI is somewhat more accurate.

Waist to height ratio

The Waist-to-Height Ratio (WHtR), is an indicator of a person's health risks. It is calculated by dividing waist circumference by height (in centimeters).

Hip circumference measurement:

Your waist is the narrowest part of your torso. The hips are below that and are usually wider than your waist. The hip measurement includes the buttocks. The hip measurement should be taken at the point where your hips are widest. Hips are the largest circumference of your lower body.

Hip circumference capture:

Hip size

Waist-to-hip ratio

The Waist to Hip Ratio (WHR) is a ratio that measures waist circumference to hip circumference. It is calculated by dividing the waist circumference by the hip circumference.

Neck circumference measurement:

Wrap the tape measure around your neck and start about three centimeters before the junction of your neck and shoulders. This can also coincide with the bottom of your Adam's apple. Go all the way around the neck and don't leave any gaps between the neck and the tape. Don't pull too hard to create unnecessary tension, just enough to get a true measurement. Make sure the tape is horizontal and not held at an angle.

Neck circumference capture:


Body fat rate

Calculation of body fat using the Navy and YMCA methods. The Navy method and the YMCA method are both methods for estimating body fat. The Navy method (also known as the 3-component model method) calculates body fat percentage based on the measurement of waist circumference, height and body weight. In addition, the formula is based on gender and age group. The YMCA method uses a simpler formula, calculated based on the measurement of height, weight and waist circumference. The formula is simpler than the Navy method, but also less accurate. Both methods are only estimates and are not very accurate, which is why it is also possible to enter the body fat percentage determined, for example, with a bathroom scale below.

It is possible to specify a body fat rate here, for example if a more accurate value than the calculated one is known from a body fat measurement. By default the Body Fat calculated according to the Navy method is used.

Body fat rate

Fat Free Mass Index (FFMI)

The Fat Free Mass Index (FFMI) is an index that goes beyond the simple BMI. BMI does not take into account the origin of weight, i.e. muscle or fat. BMI is more relevant in this case, as it takes into account body fat. A high FFMI indicates a good training condition and therefore a high proportion of muscle. The upper limit of FFMI is 25 for men and 22 for women, which is a measure of the potential that can still be achieved through training and diet. Men should aim for an FFMI above 20 and women should aim for 17.

Summary of results

Waist Circum­ference
Hip Circum­ference
Neck Circum­ference
Body Fat Percentage
Ponderal index
Broca index
Body fat Navy Method
Body fat YMCA Method

Body Mass Calculators

BMI for age: Infants 0 to 1 year Childs 1 to 5 years

BMI progress charts: BMI Charts

Body mass indices: Calculation of the Body Indices

Body Mass Tables: BMI Tables BMI Index