Calculate expected cost
At a 3% rate and $5 per attempt, the long-run expected cost is about $166.67.
Formula
Expected attempts are estimated as 1 divided by the success probability. Expected cost is expected attempts multiplied by price per attempt.
Example interpretation
At a 3% success rate, the long-run expected attempts are about 33.33. If each attempt costs $5, the expected cost is about $166.67. That number is not a target, a limit, or a promise. It is the average you would expect only across many repeated independent trials with the same rate and price.
A real person can hit the result early, miss far longer than the average, or stop before reaching the average. For random purchases, read the expected cost together with the miss chance and a fixed budget.
When not to use this calculator alone
Expected cost is less useful when the rate changes over time, attempts are not independent, prize pools are limited, pity rules apply, or the price per attempt changes with bundles. In those cases, use a tool that matches the specific model or read the official rules before making a decision.
Limitations
- Expected cost is a long-run average, not a guarantee.
- The model assumes independent attempts with a stable success rate.
- It does not handle pity systems, changing rates, discounts, taxes, shipping, resale value, or shrinking prize pools.
FAQ
Does expected cost mean I will spend exactly that amount?
No. Expected cost is a long-run average across many similar situations. A single real outcome can be cheaper or much more expensive.
Can expected cost justify buying more attempts?
No. Use expected cost to understand scale and risk, not as a reason to exceed a budget.
What happens when the success rate is very low?
The expected attempts and expected cost rise quickly. That is a sign to compare alternatives before spending.
Privacy note
The expected cost calculator runs in the browser and does not require account registration. Inputs are normal calculator values.