The count you're looking for is 18
Every standard roulette wheel has 18 black pockets. The number stays the same on both major wheel designs, but the total number of pockets does not, and that difference changes the odds on every bet you place. Before you sit down, it helps to know which wheel you're looking at.
A European wheel carries 37 pockets: the numbers 1 through 36 plus a single green zero. An American wheel carries 38: the same 1 through 36, a single zero, and a double zero. In both layouts, the 36 numbered pockets split evenly into 18 red and 18 black. The zeros are neither red nor black; they are green, and they belong to the house on the even-money bets.
So the answer to the question is simple on its face: 18 black numbers. But the reason anyone asks usually runs deeper than a count. They want to know what those black pockets mean for a bet on black, how the wheel is arranged, and whether one wheel type is better to play than the other. Those questions are worth answering properly.
What the black pockets are
The black numbers on a European wheel are 2, 4, 6, 8, 10, 11, 13, 15, 17, 20, 22, 24, 26, 28, 29, 31, 33, and 35. The red numbers are the remaining 18. The sequence is not random in the sense of being thrown together; it follows a traditional arrangement designed to alternate colors as much as possible while distributing odd and even, high and low numbers around the wheel.
On an American wheel, the black numbers are the same set. What changes is the insertion of the double zero, which sits opposite the single zero on the wheel and adds one more green pocket to the sequence. The color split among the numbered pockets stays 18 and 18.
When a player bets on black, the bet covers all 18 black pockets and nothing else. It does not cover the zeros. That is the single most important mechanical fact about the bet, because it is where the house edge on even-money wagers comes from.
Why the wheel type changes the bet
A bet on black pays 1 to 1. If the wheel had no zeros, the bet would be a coin flip: 18 winning pockets against 18 losing pockets. The zero pockets break that symmetry. On a European wheel, the ball can land in 37 pockets, and only 18 of them pay the black bet. On an American wheel, the ball can land in 38 pockets, and still only 18 pay.
That extra losing pocket is not a small detail. It is the entire mechanism by which the house earns its edge on the outside bets. The player is not betting against the casino's guess; the player is betting on a subset of pockets while the wheel contains pockets that belong to no color bet at all.
| Wheel type | Total pockets | Black pockets | Red pockets | Green pockets |
|---|---|---|---|---|
| European | 37 | 18 | 18 | 1 |
| American | 38 | 18 | 18 | 2 |
The table shows the structure plainly. The number of black pockets does not change between wheel types. The number of non-black pockets does, and that is what alters the probability of winning any color bet.
How a round plays out
Understanding the wheel is one part of sitting down correctly. The other part is knowing the rhythm of a round, because roulette moves faster than most newcomers expect.
You buy in at the table by placing cash on the layout; the dealer exchanges it for roulette chips, which are distinct from the chips used at other table games. Roulette chips carry no denomination printed on them. Each player at a table receives a unique chip color so the dealer can tell bets apart. You state a value for your chips, and the dealer marks that value on the chip rack.
Betting opens when the dealer clears the previous round and pushes the marker off the layout. You place chips directly on the felt for inside bets, or on the marked areas around the outside for bets like black, red, odd, even, high, and low. The dealer announces when betting is closing, usually with a phrase like "no more bets," and then sends the ball around the track in the opposite direction of the spinning wheel.
When the ball drops, the dealer places the marker on the winning number, sweeps losing bets off the layout, and pays winners. Outside bets like black pay 1 to 1. Inside bets pay more but cover fewer pockets. You leave your chips on the table until the dealer has finished paying; touching them before the payout is complete is the fastest way to slow down the table and annoy everyone at it.
What the zero pockets do to every bet
The zero pockets are not a side issue. They are the reason a roulette wheel is a house-banked game rather than a fair lottery among players. On a European wheel, a bet on black wins 18 times out of 37, which means it loses slightly more often than it wins. On an American wheel, it wins 18 times out of 38.
This does not mean the player is doomed on any given spin. Short runs can go heavily in either direction. But the structure of the wheel guarantees that over many spins, the house keeps the difference between the number of winning pockets and the number of losing pockets, expressed as a percentage of each wager.
The same principle applies to every bet on the layout. A straight-up bet on a single number pays 35 to 1, but there are 37 or 38 pockets, not 35. The payout is calibrated to a wheel with 36 numbers and no zeros. The zeros are the gap between the payout and the true odds.
What you control at the table
You cannot change the number of black pockets, and you cannot change the payout. What you can control is which wheel you play, how much you wager per spin, and how long you stay at the table.
The wheel choice is the most concrete decision. A European wheel has one fewer green pocket than an American wheel, which means every bet on the layout loses at a slower expected rate on the European version. The difference is structural and applies to every wager, not just the color bets.
Beyond that, roulette offers no decision points during a round. Unlike blackjack, where you decide whether to hit or stand, roulette is a game of placement. You choose a bet or combination of bets, the dealer spins, and the wheel settles the matter. The only strategic content is in bet selection and money management, not in any mid-round choice.
Common procedural mistakes at the wheel
New players tend to make the same three errors, and all of them are procedural rather than mathematical. The first is reaching for chips after the dealer has announced no more bets. Once the ball is in motion, the layout is closed. Any chip you place after the call will be returned, and repeated attempts will draw a warning.
The second is assuming the color chips have a face value. They do not. Your stack of red chips might be worth one unit each, while the player next to you has the same color chips worth five units each. The dealer tracks the values on the rack. When you leave the table, you must exchange your color chips for standard cash chips before going to the cage, because the cashier cannot redeem roulette chips.
The third is stacking bets after a win without understanding what the payout was. A win on black returns your original wager plus an equal amount in profit. If you let the full amount ride, you are now wagering twice as much on the next spin. That is a legitimate choice, but it should be a choice, not an accident.
Reading the layout before you bet
The black bet is marked clearly on the outside of the layout, usually as a black diamond or a section of felt colored black. It sits alongside the red bet, and the two are often adjacent. Placing a chip on the line between them, or on the wrong colored area, produces a different bet than the one you intended.
Inside the number grid, the black numbers alternate with red numbers in a checkerboard pattern. The zeros sit at the top of the grid, green and unnumbered on some layouts, marked with a single or double zero on others. The arrangement of the grid does not match the arrangement of the wheel; the grid is sequential, while the wheel is arranged to balance the colors and number properties around the track.
Before you place any bet, confirm the table minimum and maximum. Outside bets like black often carry a higher minimum than inside bets, and the maximum applies to each betting position separately. The dealer can tell you the limits, and they are also printed on a sign at the table.
FAQ
Do the black numbers differ between European and American roulette?
No. The set of 18 black numbers is identical on both wheel types. What differs is the total number of pockets: 37 on a European wheel and 38 on an American wheel, with the American version adding a double zero.
Does betting on black give you a 50/50 chance?
Not exactly. On a European wheel, black wins on 18 of 37 pockets, which is slightly less than half. On an American wheel, it wins on 18 of 38. The green zero pockets are the reason the bet is not an even proposition.
Why are the zero pockets green instead of red or black?
The zeros are excluded from the color bets by design. Making them green signals that they belong to neither the red nor the black wager, and that a bet on either color loses when the ball lands in a zero pocket.
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This article is general information about how these mechanics work. It is not legal advice and not a recommendation to gamble or to use any particular operator. Availability and legality differ by jurisdiction — check the rules that apply where you are.