How to Use the Probability Game Expected Return Calculator
Enter the entry fee, prize amount, and win probability to instantly see four key metrics. Expected Value (EV) shows the average gain or loss per play — a negative value means you lose money over many plays. Return Rate compares your expected payout to your total investment; below 100% means long-term losses.
Plays for 50% Win Chance tells you how many times you need to play before your cumulative probability of winning at least once reaches 50%. Max Break-Even Plays shows the maximum number of plays where a single win still covers all your entry costs. Use this for lotteries, gacha games, casino games, or any event with a known prize and probability.
Frequently Asked Questions
Not in the short term — EV is a statistical average over many plays. Short-term variance can still cause losses even with positive EV.
It means you expect to get back exactly what you put in over the long run. Below 100% means net loss, above 100% means net gain.
Lotteries, casino games, gacha/loot boxes, sports betting, raffle draws — any game with a known prize and probability.