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OSRS Drop Rate Formula:
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The OSRS (Old School RuneScape) drop rate formula calculates the probability of receiving at least one drop after multiple attempts. It's based on the binomial probability formula and is essential for understanding drop mechanics in the game.
The calculator uses the OSRS drop rate formula:
Where:
Explanation: The formula calculates the complement of the probability of not getting the drop in all attempts.
Details: Understanding drop probabilities helps players estimate how many attempts they might need for rare items, plan their gameplay time, and set realistic expectations for item acquisition.
Tips: Enter the drop probability per attempt (as a decimal between 0-1) and the number of attempts. For example, for a 1/100 drop rate, enter 0.01 for p.
Q1: What's the difference between drop rate and drop chance?
A: Drop rate refers to the probability per attempt (p), while drop chance typically refers to the overall probability (P) after multiple attempts.
Q2: Does killing more monsters increase my chance per kill?
A: No, each kill is an independent event with the same probability. However, more attempts increase the overall chance of getting at least one drop.
Q3: What is the dry streak probability?
A: The probability of not getting a drop after k attempts is (1-p)^k. For a 1/100 drop rate, the chance of going 200 kills dry is (0.99)^200 ≈ 13.4%.
Q4: Are drop rates truly random in OSRS?
A: Yes, OSRS uses a random number generator for drops, making each attempt independent with no "pity" system.
Q5: How accurate is this calculator for actual gameplay?
A: This provides the mathematical probability, but actual results may vary due to RNG. It's most useful for estimating probabilities over large numbers of attempts.