In fact, the Healthy Body Calculator® does just that, if you enter your current % body fat and / or a goal even if you just want to maintain your current body fat level. Then the calculator won’t perform the average body weight calculation or a BMI. Did you read the text on page 2 below the % body fat and on page 3 below the % body fat calculation that explains this?
I formerly taught sports nutrition at the university and worked with collegiate football and hockey players who turned pro or entered the Olympics as well as body builders. That is why I designed the Healthy Body Calculator® to work for athletes as well as average people and body builders who have a lean body fat.