My project for Physical Education was to create a calculator to help figure out your basal metabolic rate and total daily energy expenditure. I researched algorithms to figure out fat and muscle mass from simple body measurements like waist circumference, and used them to create a calculator for figuring out your basal metabolic rate.

As it only needs simple measurements and uses predictions to find your fat and muscle mass, it's a lot easier to use than most calculators while providing (at least) a very good ballpark! The final calculator uses multiple algorithms, and shows you each result independently, so you can assess which results are likely to be the most accurate.

Many of the selected algorithms for this calculator are in use today by researchers and nutritionists, with lots of independent studies analyzing and comparing their accuracy.