Independent site. CasinoCalcs is not affiliated with or endorsed by Ireland’s National Lottery, Premier Lotteries Ireland or any bookmaker. Game names are used only to describe the rules the maths is based on.
- Maths reviewed by Josh Miller
- Tested by Diana Westfield
A £1 bet on three numbers at 650/1 pays £651 if all three come out of the Irish Lotto draw. The CasinoCalcs Irish Lotto bet calculator above shows that, and the part the price board doesn’t: the true chance is 1 in 709.5, so the bookie keeps about 8p in every pound. This free calculator also handles perms, where you pick more numbers and back every combination, and settles them after the draw.
Irish Lotto bet calculator: true odds vs the bookie’s price
These bets are fixed-odds bets on the official draw, six balls from 45. The prices below are examples only. Every bookmaker sets its own, so type the one on your slip.
| Numbers | True chance (6 balls) | Fair odds | Example price | Example with bonus ball |
|---|---|---|---|---|
| 1 | 1 in 7.5 | 6.5/1 | 5/1 | 4/1 |
| 2 | 1 in 66 | 65/1 | 60/1 | 40/1 |
| 3 | 1 in 709.5 | 708.5/1 | 650/1 | 350/1 |
| 4 | 1 in 9,933 | 9,932/1 | 7,000/1 | 3,000/1 |
| 5 | 1 in 203,627 | 203,626/1 | 125,000/1 | 40,000/1 |
The pattern is worth knowing. The more numbers you need, the bigger the gap between fair odds and the price. On a 5-number bet, nearly 40% of the true value can be missing.
Perms: every combination in one go
Pick six numbers and play them in trebles and you’ve got 20 three-number bets. At £1 each that’s £20. If three of your six come out, one treble wins: £651 back. If four come out, four trebles win: £2,604. Set the numbers you pick, the bet size and how many came up, and the calculator does the counting. It’s the same maths as the lottery wheel generator, just with bookie odds instead of prize tiers.
Is it better than buying a ticket?
Different, not better. A lottery ticket pays prizes from a pool, so the return depends on how many people share it. A bookmaker bet pays a fixed price, no matter how many others picked the same numbers. For the draw itself, the Irish Lotto odds calculator covers every prize tier, and the bookmaker margin calculator explains the ‘bookie keeps’ figure.
Betting on the 49s draw instead? The 49s bet calculator works the same way, with 49 balls and the Booster.
Number bets are pure chance with a built-in margin. Stake small. BeGambleAware.org is free and confidential if it stops being fun.