A roulette wheel has either 37 or 38 numbers, depending on the variation:

• European (single-zero) roulette wheel: 37 numbers, including 0 and numbers 1 through 36

• American (double-zero) roulette wheel: 38 numbers, including 0, 00, and numbers 1 through 36

The European wheel has one green zero pocket, while the American wheel has two green pockets, 0 and 00. The remaining numbers 1 to 36 are split evenly between red and black colors. The number sequences on the wheels are arranged in a specific, non-consecutive order to balance colors, odds, and high/low numbers, enhancing unpredictability

. In summary:

• European wheel: 37 numbers (0-36)
• American wheel: 38 numbers (0, 00, 1-36)