Compare calculators
Both calculators run independently — change the inputs on either side to compare results.
Probability
Geometric Probability Calculator
Find the probability that the first success occurs on exactly the nth trial, given a constant success probability per trial. Use it for modeling first-time events like the first defective item on a production line or the first sale made by a salesperson.
Fill in the required fields to see your result.
Probability
Dice Roll Probability Calculator
Compute the probability of rolling any target sum with any number of multi-sided dice. It counts the favorable combinations and divides by all equally likely outcomes, which is perfect for board-game and tabletop RPG design.
Fill in the required fields to see your result.
Key differences
| Geometric Probability Calculator | Dice Roll Probability Calculator | |
|---|---|---|
| Category | Probability | Probability |
| Inputs required | 2 | 3 |
| Result | Probability of First Success | Probability |
| What it does | Find the probability that the first success occurs on exactly the nth trial, given a constant success probability per trial. Use it for modeling first-time events like the first defective item on a production line or the first sale made by a salesperson. | Compute the probability of rolling any target sum with any number of multi-sided dice. It counts the favorable combinations and divides by all equally likely outcomes, which is perfect for board-game and tabletop RPG design. |