Check what counts as a roll
Enter the probability for one eligible attempt. A boss kill with an exhausted lockout may produce zero eligible attempts, and a chest can sometimes have multiple rolls.
Calculate the complement
If one roll has a 5% chance of success, it has a 95% chance to miss. Ten independent retries all fail with probability 0.95 to the power of 10. Subtract that from one for the chance of at least one success.
Account for changing rates separately
Guarantees, pity or a changing pool change the miss probability. The calculator assumes the same chance on every attempt. Use a distinct model if the rates change.