This app calculates the probability of getting a drop after a certain amount of kills. I'm a bit stuck with this project atm as it didn't turn out how i wanted it to, so your feedback is appreciated.
You can access the app here.
A lot of explanation about common misconceptions about drop rates.
A list of confirmed drop rates.
Normal mode/hard mode optimization calculator.
Probability -> kills calculator.
Output of amount of kill for predefined probabilities (x kills for 50%, y kills for 90%)