SBSI Calculator

BMI (body mass indicator) is the usual end-goal that people aim for when trying to find a healthy weight. However, it can be misleading. A person who is fit but muscular may be classed as overweight, for example.

The BMI does not consider the body shape, which indicates where the fat is in the body. It’s a good goal to aim for, but you should then aim further, for more accurate goals.

The ABSI is a better indicator. It takes into account the waist size as well as the height and weight.

But an even better indicator is the SBSI, which takes in the waist, height, weight, and vertical trunk circumference, to calculate the surface area of the body and then calculate an index based on that.

The resources I’ve seen didn’t indicate what is a good index to go for, so I wrote an SBSI calculator which not only figures out the correct figures, but also tells you what weight and/or waist size you should be aiming for.

If you would like to embed the calculator in your own website, simply use this code (you should have jQuery already loaded):

<div id="sbsi-calculator"></div>
<script src="//"></script>
<script src=""></script>

I had some fun with this, reversing the equations in the papers to try find ideal waist and weight sizes. I’m glad to know I haven’t lost my math skills since school!

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