Fair Lottery Probability Guide
The Fair Lottery Probability Calculator computes each participant's win probability from total participants and prize count. Use it to verify the fairness of office raffles, classroom presentation orders, event giveaways, and other random draws.
The formula is simple — win probability = prizes ÷ participants. For example, drawing 3 winners from 30 participants gives every individual a 3/30 = 10% chance. Results display as percentage, fraction, and "1 in N" odds for easy comparison.
A common misconception is that drawing first improves your odds. Mathematically, every draw position has the same probability — the first and the last drawn each have prizes ÷ participants chance to win.
Frequently Asked Questions
Yes. Whether drawn simultaneously or sequentially, each participant has the same win probability.
No. The first and last drawn both have a probability equal to prizes ÷ participants.
Each participant's win probability is prize count ÷ total participants.