Birthday Bet
November 5th, 2025 at 4:22:28 PM
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I just saw an ad for Birthday Bet, a roulette side bet in Vegas.
The Wizard of Odds site says it initially pays 6:1 but pays 50:1 on subsequent rolls, but the text in this ad said it initially pays 5:1 and then 70:1.
I calculated the RTP to be around 86.8%
Math: (5)*((3/38)^1) +(70)*((3/38)^2) +(70)*((3/38)^3) +(70)*((3/38)^4)…
I don’t think that the Wizard of Odds website has the house edge right for the 6:1 variant. Can someone else take a look? I think the math is off - landing this bet on the roulette wheel twice should earn you 56 not 50…
The Wizard of Odds site says it initially pays 6:1 but pays 50:1 on subsequent rolls, but the text in this ad said it initially pays 5:1 and then 70:1.
I calculated the RTP to be around 86.8%
Math: (5)*((3/38)^1) +(70)*((3/38)^2) +(70)*((3/38)^3) +(70)*((3/38)^4)…
I don’t think that the Wizard of Odds website has the house edge right for the 6:1 variant. Can someone else take a look? I think the math is off - landing this bet on the roulette wheel twice should earn you 56 not 50…
November 5th, 2025 at 7:12:08 PM
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Quote: harrisI just saw an ad for Birthday Bet, a roulette side bet in Vegas.
The Wizard of Odds site says it initially pays 6:1 but pays 50:1 on subsequent rolls, but the text in this ad said it initially pays 5:1 and then 70:1.
I calculated the RTP to be around 86.8%
Math: (5)*((3/38)^1) +(70)*((3/38)^2) +(70)*((3/38)^3) +(70)*((3/38)^4)…
I don’t think that the Wizard of Odds website has the house edge right for the 6:1 variant. Can someone else take a look? I think the math is off - landing this bet on the roulette wheel twice should earn you 56 not 50…
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I get the house edge at ~18.8% for the original 6:1, 50:1 version, I believe the intention of the bet according to the rack card is to be an infinite series, so you keep getting paid 50 to 1 on subsequent hits until you lose, but ultimately you always lose so I subtract one from the total pay.
| Hits | Probability | Payout | Expected Value |
|---|---|---|---|
| 0x | 0.921052632 | -1 | -0.921052632 |
| 1x | 0.072714681 | 5 | 0.363573407 |
| 2x | 0.005740633 | 55 | 0.315734801 |
| 3x | 0.000453208 | 105 | 0.047586824 |
| 4x | 3.57796E-05 | 155 | 0.005545833 |
| 5x | 3.06682E-06 | 205 | 0.000628698 |
| 6x | 2.42117E-07 | 255 | 6.17399E-05 |
| Total | -0.187921328 |
Out of curiosity, where did you see an ad for it at? I don't see a lot of promotional stuff around games and/or sidebets.
November 5th, 2025 at 8:09:01 PM
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I also got that house edge in a slightly different way
(6)*((3/38)^1) +(50)*((3/38)^2) +(50)*((3/38)^3) +(50)*((3/38)^4) + (50)*((3/38)^5)...
Modifying this equation by changing 38 to 39, and changing 6 or 50 can yield the 30 other possible pay tables that exist according to Nevada law.
(6)*((3/38)^1) +(50)*((3/38)^2) +(50)*((3/38)^3) +(50)*((3/38)^4) + (50)*((3/38)^5)...
Modifying this equation by changing 38 to 39, and changing 6 or 50 can yield the 30 other possible pay tables that exist according to Nevada law.
November 5th, 2025 at 8:10:23 PM
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In retrospect it probably wasn't an ad, my social media is just cooked and I get recommended a ton of gambling content on Instagram and Youtube. The casino is Rio btw and you can watch their video on instagram. I scrolled through their instagram and the only other table games content I saw was craps I think
