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Wondering how many missions or enemy kills you might need for a drop? Check the difference between average attempts and the attempts needed for a high chance of success. This calculator uses the planner API and needs an internet connection.
Enter the per-attempt drop chance shown in the game or a verified drop table. Every attempt is assumed to be independent and to award at most one copy.
Calculating attempts…
Suppose an item has a 10% independent drop chance per run and you need one copy. The average wait is 10 runs, but the chance of obtaining it within 10 runs is only about 65%. To reach a 90% chance, plan for 22 attempts. Even then, about one in ten players would still need more attempts.
For one copy, the chance of at least one success in n independent attempts is 1 − (1 − p)n, where p is the chance per attempt. For multiple copies, the calculator uses the binomial distribution to find the chance of at least the requested number of successes.
It assumes each attempt is independent, has an unchanged probability, and awards at most one copy. It does not model rotating reward pools, varying drop conditions, squad relic choices, trade costs, or missions giving several copies at once. A mission completion may not be the same as a single drop roll; check the source of the displayed drop rate.
For actual item-specific drop sources and combined farming plans, use the Warframe Farming Planner. Check the latest official Warframe drop tables for probabilities: this page does not invent or automatically fetch drop rates.