Roulette Spin Tracker
Log every spin, visualize hot and cold numbers, track streaks, and analyze distribution patterns. Your data stays private, everything runs client-side.
Number Input
Understanding Roulette
Roulette Odds Explained
| Bet Type | Payout | European | American |
|---|---|---|---|
| Straight Up (single number) | 35:1 | 2.70% | 2.63% |
| Split (2 numbers) | 17:1 | 5.41% | 5.26% |
| Street (3 numbers) | 11:1 | 8.11% | 7.89% |
| Corner (4 numbers) | 8:1 | 10.81% | 10.53% |
| Six Line (6 numbers) | 5:1 | 16.22% | 15.79% |
| Dozen / Column | 2:1 | 32.43% | 31.58% |
| Red/Black, Odd/Even, High/Low | 1:1 | 48.65% | 47.37% |
The Gambler's Fallacy
The Gambler's Fallacy is the mistaken belief that past outcomes influence future results. If red hits 10 times in a row, the probability of the next spin being red remains exactly the same, 48.65% on European wheels. The wheel has no memory.
This fallacy drives systems like Martingale, where players double bets after losses expecting a "correction." In reality, the house edge applies to every single spin equally. Long streaks are statistically normal. In 1000 spins, you should expect at least one streak of 8+ consecutive reds or blacks.
European vs American
The single zero on a European wheel gives a house edge of 2.70%. The American wheel adds a double zero (00), nearly doubling the house edge to 5.26%. Over 1,000 bets of $10 on even-money bets:
- European: Expected loss of $270 (2.70% × $10,000)
- American: Expected loss of $526 (5.26% × $10,000)
- Difference: $256 more lost on American over the same session
Always prefer European roulette when available. Some European tables also offer the "La Partage" or "En Prison" rules, which further reduce the house edge on even-money bets to 1.35%.
Why Tracking Does Not Give an Edge
Every roulette spin is an independent event. The ball and wheel have no memory of previous outcomes. Tracking spins cannot reveal patterns that predict future results because no such patterns exist in a fair game.
The only scenario where tracking could theoretically help is if a physical wheel had a manufacturing defect causing genuine bias, something casinos test for extensively with automated systems. Modern wheels are precision-engineered and regularly inspected.
This tracker is useful for record-keeping, entertainment, and learning about probability through real data, not for developing a "winning system." The math is clear: the house always has the edge.
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