The wheel you sit down at decides the answer
A roulette wheel is not a single standard object. Walk into a casino and the wheel in front of you will be one of two layouts, and the difference is not cosmetic. A European wheel carries 37 pockets: the numbers 1 through 36 plus a single zero. An American wheel carries 38: the same 1 through 36, a single zero, and a double zero. The extra pocket is not a tiebreaker or a neutral space. It changes the arithmetic on every bet you can place.
The numbered pockets run from 0 to 36 on both wheels. The zero, and the double zero where present, are coloured green. The other 36 numbers alternate red and black around the wheel. The sequence of numbers around the rim differs between the two wheel types, but the set of numbers available to bet on is the same except for the double zero.
When someone asks how many numbers roulette has, the practical answer is: check the wheel before you buy in. If there is a double zero on the layout, you are looking at an American wheel with 38 pockets. If there is only one zero, it is a European wheel with 37. Some venues offer both, and some online lobbies carry both variants side by side. The wheel type is printed on the table layout and shown in the game information panel online, so you do not need to count pockets by eye.
Why one extra pocket matters more than it looks
A single extra pocket sounds trivial. On a 38-pocket wheel, the double zero is one space out of 38. But roulette pays winning bets as if the zero pockets did not exist. A straight-up bet on a single number pays 35 to 1. On a European wheel, the true odds against hitting that number are 36 to 1, because there are 37 pockets and only one wins. On an American wheel, the true odds are 37 to 1, because there are 38 pockets. The payout stays at 35 to 1 either way. That gap between the payout and the true odds is the house edge, and the double zero widens it on every bet on the layout.
The comparison between the two wheel types is clearest as a table:
| Feature | European wheel | American wheel |
|---|---|---|
| Number of pockets | 37 | 38 |
| Zero pockets | Single zero only | Single zero and double zero |
| Number range | 0 to 36 | 0 to 36 plus 00 |
| True odds against a single number | 36 to 1 | 37 to 1 |
| Payout on a single number | 35 to 1 | 35 to 1 |
| Effect on house edge | Lower edge on the same bet type | Higher edge on the same bet type |
The table shows the mechanism rather than a slogan. The payout column is identical. The odds column is not. The house keeps the difference between the two, and that difference is larger on the American layout for every bet that pays less than the true odds, which is every standard bet on the table.
The object of the game and the sequence of a round
Roulette is a game of prediction against a wheel, not against other players. You are wagering on where a ball will come to rest after the wheel is spun. The objective is to place a bet that covers the winning pocket. There is no hand to beat, no dealer total to compare, and no decision to make after the spin begins. Every decision happens before the ball is released.
A round moves through a fixed sequence. First you buy in: you hand the dealer cash or a casino chip voucher and receive roulette chips. Roulette chips are typically a distinct colour per player so the dealer can tell whose bets are whose on the shared layout. These chips have no value printed on them; their value is set at the table when you buy in, and the dealer places a marker on the rim showing what each chip is worth.
Second, you place bets on the layout. The layout is a printed felt showing the numbers and the outside betting areas. You can bet on a single number, a split between two numbers, a street of three, a corner of four, a line of six, or the outside areas covering red or black, odd or even, high or low, dozens, and columns. Each bet type has its own payout and its own true odds, and the house edge differs across them on some layouts.
Third, the dealer closes betting. In a physical casino the dealer announces that no more bets may be placed, then spins the wheel and releases the ball in the opposite direction. Online, the betting window closes on a timer. Fourth, the ball settles in a pocket. The dealer marks the winning number on the layout with a marker, clears losing bets, and pays winning bets. Your chips are then available for the next round or for colouring up back into value chips at the cashier.
What each decision point means
The only real decision in roulette is what to bet before the spin. That decision is a choice about two things: how many numbers you want to cover, and how much variance you are willing to accept in exchange for the payout shape. A straight-up bet on one number pays 35 to 1 and wins rarely. A bet on red pays even money and wins close to half the time on a European wheel, slightly less than half on an American wheel because the zero pockets are neither red nor black. Neither choice changes the house edge in your favour. What changes is how the losses are distributed across a session.
Covering more numbers does not improve the expected result. A common move is to spread chips across many numbers so that something wins on most spins. The problem is that the payouts are sized for the true odds, minus the house edge. If you cover 20 numbers on a European wheel, you win on 20 of 37 spins, but the amount you collect on a win is smaller than the total you laid out across all 20 spots. The uncovered numbers and the zero take the whole stake. The edge remains built into each individual bet, and combining bets does not cancel it.
The outside bets carry the same house edge as the inside bets on a European wheel for the standard even-money and 2-to-1 areas. That changes on an American wheel only in the sense that the double zero raises the edge across the board. There is no bet on the layout that turns the arithmetic around. The choice is between a rarer, larger payout and a more frequent, smaller one, and that is a volatility choice, not an edge choice.
Bet types and how their edges compare
Roulette bet types differ in payout, in how often they win, and in the specific house edge attached to each. The table below compares the main bet types on a European wheel. The American wheel raises the edge on every row because the double zero is an additional losing pocket that does not increase any payout.
| Bet type | Numbers covered | Payout | What changes for the player |
|---|---|---|---|
| Straight-up | 1 | 35 to 1 | Rare wins, large payout, high variance |
| Split | 2 | 17 to 1 | Slightly more frequent wins, smaller payout |
| Street | 3 | 11 to 1 | Three-number coverage on one row |
| Corner | 4 | 8 to 1 | Four-number coverage on a square |
| Six line | 6 | 5 to 1 | Two adjacent rows covered at once |
| Dozen or column | 12 | 2 to 1 | Wins on roughly a third of spins on a European wheel |
| Red/black, odd/even, high/low | 18 | 1 to 1 | Wins close to half the time, but the zero pockets are uncovered |
The table lists what the player can control: coverage and payout shape. It does not list a row where the house edge disappears, because no such row exists. On an American wheel the same table holds, but every bet loses slightly more often because the double zero sits outside every listed category except a direct bet on it.
Where the edge lives and what a session looks like
The house edge in roulette is not hidden in the wheel's spin. It is visible in the gap between the payout and the true odds. On a European wheel, a straight-up bet pays 35 to 1 when the true odds are 36 to 1. That one-unit gap, spread across all 37 pockets, is the operator's mathematical advantage on that bet. The same structure applies to every other bet. The wheel does not remember previous spins, and no pocket becomes more likely because it has not appeared recently. Each spin is an independent event under the random number generator or the physical wheel's mechanics.
A session of roulette is a series of independent negative-expectation bets. Short runs will produce winning sessions and losing sessions, sometimes dramatically in either direction. Over a large number of spins, the results converge toward the house edge. That is what the Return to Player percentage describes: a long-run statistical average, not a per-session promise. A game with a lower house edge loses money more slowly on average than a game with a higher one, all else equal, but neither produces a positive expectation for the player.
The procedural mistakes new players make are mostly about the table's mechanics rather than the maths. The first is buying in mid-round: placing cash on the table while the ball is already spinning forces the dealer to stop and exchange chips, and most tables require you to wait until the current round settles. The second is touching your chips after the dealer calls no more bets. Once betting closes, any chip movement can be read as an attempt to alter a wager, and the dealer will correct it or void the bet. The third is not knowing the value of your own colour chips. Because roulette chips carry no printed denomination, a player who forgets the buy-in value can misread a stack and overbet without realising it until the payout comes back short.
FAQ
Does the zero count as a number in roulette?
Yes. The zero is a pocket on the wheel and a betting option on the layout, and it counts toward the total. A European wheel has 37 pockets because the numbers 1 through 36 are joined by a single zero. An American wheel has 38 because both a single zero and a double zero are present.
Which roulette wheel should I choose if both are available?
If the choice is between a European and an American layout at the same venue, the European wheel carries the lower house edge on the same bet types because it has one fewer zero pocket. The decision is still a choice between negative-expectation games, but the rate of expected loss differs, and that difference is real over a long session.
Why does the American wheel exist if it has worse odds for the player?
The double zero is a historical feature of roulette as it developed in different regions, and it remains in use because it is the standard layout in many venues. The extra pocket increases the operator's mathematical advantage on every bet, which is why the wheel type is printed clearly on the layout and in the game information panel online.
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