Enter one option per line as Name, weight, check the odds table, then press Pick Winner to draw an entry with those probabilities.
Write one option per line as Name, weight — for example 'Alice, 3'. Alice then gets three entries against a line with weight 1. A line with no weight is treated as weight 1.
All weights are added up, a secure random point is picked in that total, and the tool walks the list until it reaches that point. That gives each option a probability of exactly its weight divided by the total.
Yes. The table shows every option with its weight and its exact percentage chance, so you can sanity-check the setup before you draw.