Agriculture Fertilizers Calculator and Multi Convertor for Farmers and Agriculture Students. <>. This app is available in three languages :- English, Punjabi and Hindi. <>. In this Calculator:- You can Calculate the Fertilizer required dose by applying of recommended dose of NPK... here you can find fertilizer dose in Urea, Super Phosphate, MOP.. You can also find other source of Phosphorus like DAP instead of Superphosphate. This is advance Calculator for Fertilizers for Farmers and students.