← Calculators
Drop rate calculator
Works for any OSRS drop, pet or clue reward on a flat 1-in-X rate. Enter the rate and how
many kills/attempts you've done.
Enter a drop rate and kill count.
Kills needed for a given chance
Enter a drop rate above.
OSRS drop rate calculator — dry streaks and pets
Enter a drop rate and your kill count to see your chance of having received the drop by now, how unlucky a dry streak is, and how many kills you need for a 50%, 90% or 99% chance. Works for any boss drop, pet or clue reward.
Frequently asked questions
How do I calculate my chance of a drop?
For a 1-in-N drop over k kills, the chance of at least one is 1 − (1 − 1/N)^k. This tool does the maths and also shows the kills needed for 50%, 90% and 99% certainty.
What does 'going dry' mean?
Getting far more kills than the drop rate without receiving the drop. The calculator tells you exactly how unlucky (what percentile) your current dry streak is.