Fddb calculates the daily requirement using the so-called Harris-Benedict formula. If you have specified sporting activities in your profile, they will also be included in the calculation.
Fddb estimates your daily requirement as well as possible. However, everyone is different. Your real daily requirement can be higher or lower. If you do competitive sports or have special illnesses, the calculated daily requirement will differ greatly from your real daily requirement. In your profile you also have the option of freely specifying your daily requirement. Please also read our notes on health topics.