Reverse Body Mass Index Calculator

This formula is the same as BMI, except we swap the traditional method of interpreting it into a different perspective. The RBMI can be helpful for certain research purposes or as a rethinking of traditional body weight metrics.

To clarify things further, here’s how the different BMI ranges correlate with their RBMI counterparts.

BMI Categories and Corresponding RBMI:

BMI Category	BMI Range	RBMI Value Range (inverse)
Underweight	< 18.5	> 25
Normal Weight	18.5 – 24.9	20 – 25
Overweight	25 – 29.9	17 – 20
Obesity Class I	30 – 34.9	13.5 – 17
Obesity Class II	35 – 39.9	12.5 – 13.5
Obesity Class III (Severe)	≥ 40	< 12.5

What Does Reverse BMI Represent?

In simpler terms:

• Higher RBMI values are indicative of being underweight.
• Lower RBMI values correspond to being in the overweight or obese categories.

For instance:

• If someone has an RBMI value higher than 25, they might be considered underweight based on the traditional BMI scale.
• If someone has an RBMI lower than 12.5, they might fall into the obesity category (class III).

Example Calculations:

To calculate the RBMI for a person, follow these steps:

1. Example 1:
   • Weight: 70 kg
   • Height: 1.75 m
   • RBMI = 70 / (1.75)^2 = 22.86
   This person falls into the normal weight category based on the RBMI.
2. Example 2:
   • Weight: 50 kg
   • Height: 1.5 m
   • RBMI = 50 / (1.5)^2 = 22.22
   This person also falls into the normal weight category.