# Broca Index Calculator

Determines ideal body weight based on height and gender.

Refer to the text below the tool for more information on the Broca Index.

The Broca Index, also known as the Broca formula was devised back in 1871 by the French physician, surgeon and anthropologist Paul Broca, as a measure of the normal weight of a person.

Whilst new indicators such as BMI or Ponderal Index have been developed since, the Broca Index remains a good method for middle aged populations of average body sizes to estimate ideal body weight due to its simplicity and use of only one standard measurement.

• Broca Index Normal Weight = Body Height – 100
• Ideal Weight (Men) = (Height – 100) – (Height – 100) x 10%
• Ideal Weight (Women) = (Height – 100) + (Height – 100) x 15%

Where: Height is expressed in centimeters.

Height
Gender
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Steps on how to print your input & results:

2. Then you can click on the Print button to open a PDF in a separate window with the inputs and results. You can further save the PDF or print it.

Please note that once you have closed the PDF you need to click on the Calculate button before you try opening it again, otherwise the input and/or results may not appear in the pdf.

## The Broca Index Explained

The Broca Index, also known as the Broca formula was devised back in 1871 by the French physician, surgeon and anthropologist Paul Broca, as a measure of the normal weight of a person.

• `Broca Index Normal Weight = Body Height – 100`
• `Ideal Weight Male = (Height – 100) – (Height – 100) x 10%`
• `Ideal Weight Female = (Height – 100) + (Height – 100) x 15%`

Where: Body height is expressed in centimeters.

The Broca Index formed the benchmark for other body calculations in use today but is now considered outdated and usually replaced in practice by the body mass index (BMI).

However, due to their simplicity and rapidness of use, these formulas remain a good method for middle aged populations of average body sizes to estimate ideal body weight. For very large and very small body sizes, the BMI is somewhat more precise.

The main limitations of Broca Index are linked to the fact that it only applies one standard measurement in the calculation (i.e. height) and also that it may not be as specific for height outliers and not accurate in infants.

## References

### Original reference

Broca P. Mémoires d'anthropologie. Paris: C Reinwald. 1871.

### Validation

Weber-Sanchez A, Ortega Sofia V, Weber-Alvarez P. Validation of the Broca index as the most practical method to calculate the ideal body weight. J Clin Invest Stud 1: 2018.

### Other references

Nahler G. Broca-formula. In: Dictionary of Pharmaceutical Medicine. Springer. 2009; Vienna.

Mundodan JM, Saju CR, Joshy VM. Utility of Broca’s Index in Assessing Body Mass: Analysis of Anthropometric Measures from A Cross Sectional Study. Natl J Community Med. 2019; 10(11): 600-604.

Specialty: Fitness

Year Of Study: 1871

Article By: Denise Nedea

Published On: June 8, 2020 · 12:00 AM

Last Checked: June 8, 2020

Next Review: June 8, 2025