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- Maths reviewed by Josh Miller
- Tested by Diana Westfield
A tombola odds calculator settles the argument at every school fête: “I bought five tickets and won nothing, it must be rigged.” Probably not. If tickets ending in 0 or 5 win, each one has a 1 in 5 chance, and five tickets give you about a 67% chance of at least one prize. A third of five-ticket buyers walk away empty-handed. The free CasinoCalcs calculator shows the real numbers for any drum.
Tombola odds when you buy more tickets
Here’s a drum of 500 tickets with 100 winners, the usual 0-or-5 rule:
| Tickets you buy | Chance of at least one prize | Prizes you’d expect |
|---|---|---|
| 1 | 20.0% | 0.2 |
| 3 | 48.9% | 0.6 |
| 5 | 67.4% | 1.0 |
| 10 | 89.5% | 2.0 |
| 20 | 99.0% | 4.0 |
“One prize on average” for five tickets doesn’t mean one prize each time. Some people get two or three and plenty get none. The drum also empties as the day goes on, so the odds shift slightly with every ticket drawn. The calculator allows for that: tickets aren’t put back.
Running the stall
If you’re the one with the drum, flip it round. You need a prize for every winning ticket, so a 1 in 5 tombola with 500 tickets needs 100 prizes. Raffle tickets from a cloakroom book are cheap, and anything donated (bottles, toiletries, tins of biscuits) is profit. At £1 a ticket, a full drum makes £500 before any prizes you had to buy.
Want a smaller stall? A 1 in 4 rule with 200 tickets needs 50 prizes and feels generous. For a raffle with bigger prizes, see the raffle odds calculator and raffle ticket price calculator. For bingo at the same event, the bingo caller runs the game for you.
Planning a fundraiser night? The race night odds calculator and the penny raffle calculator handle two more crowd favourites.