1. Select the size of your die 2. Select the number of dice you would like to roll 3. Select if the target numbers are above or below (i.e. some games will say 4+ or 4-) 4. Select what the cut-off is (i.e. 2+, 3-, 5+ etc) 5. You can also choose to re-roll 1s if you chose + or 6s if you chose -. 6. Click GO to roll the dice and the number that passed the cut off will appear in the bottom left-hand corner. You can click on the Made it List and the Didn't Make it List button to show the exact die rolls that made the cut off and those that did not. The probability of how likely it is that each die will pass is also calculated and the probable amount of dice that will pass. When re-rolling 1's/6's the percentage won't change because each die still has the same likelihood of passing but not you are re-rolling some so the expected number will change. This is either calculated when you click GO or the P button. You can either reset by clicking the flag or the red reset button in the bottom right-hand corner.
https://forkphorus.github.io/#401169675 This will let you save this as a local file and run it more smoothly There are also a few short cuts that I often use. You can easily customize these by opening up the code and going to their sprites. One is blank just for this purpose. Feel free to remix this so you can customize it to better suit your gaming needs. I tried to label everything to make understanding it pretty straight forward.
