Count the Pockets Before You Buy In
You sit down at a roulette table, and the first thing you notice is the wheel. Most of the pockets alternate red and black, but there is always at least one pocket that is neither. That green pocket is small on the wheel and enormous in the maths. Before you place a single chip, you want to know exactly how many pockets of each colour you are betting against, because the answer changes with the wheel in front of you.
A standard roulette wheel has 36 numbered pockets, running from 1 to 36. Of those, 18 are red and 18 are black. The numbers are not arranged by colour in sequence around the wheel; the alternation is deliberate, but the colours are assigned to specific numbers and never change. The red numbers are 1, 3, 5, 7, 9, 12, 14, 16, 18, 19, 21, 23, 25, 27, 30, 32, 34 and 36. The black numbers are 2, 4, 6, 8, 10, 11, 13, 15, 17, 20, 22, 24, 26, 28, 29, 31, 33 and 35. That is the constant part.
The variable part is the zero. A European-style wheel has a single green zero, which makes 37 pockets in total. An American-style wheel adds a double zero, also green, which makes 38. The red and black count stays at 18 each on both wheels. What changes is the proportion of the wheel that is not red or black, and that proportion is the entire source of the operator's built-in advantage on the colour bets.
Why the Green Pocket Changes Every Bet
A bet on red or black pays even money. If the wheel had no zero, the bet would be a fair coin-flip: 18 winning pockets against 18 losing pockets. The zero breaks that symmetry. On a European wheel, your red bet has 18 winning pockets out of 37 total. The remaining 19 pockets lose. The difference between those two numbers, expressed as a share of the total, is the house edge on that bet.
On an American wheel, the same red bet has 18 winning pockets out of 38, with 20 losing. The extra green pocket does not change what you win when red lands; it only adds another way to lose. That is why the American layout carries a larger built-in edge on the same bet. The colour count is identical on both wheels, but the odds are not.
This is the cleanest way to read any roulette table. Count the green pockets first. They are the only part of the wheel that is not covered by the red-black, odd-even or high-low bets. Every other bet on the layout is priced around those pockets.
The Round, From Buy-In to Settlement
You buy in by placing cash on the table, not by handing it to the dealer. The dealer exchanges it for roulette chips. These are different from the chips at other tables: they carry no printed denomination, and each player at the table gets a distinct colour so the dealer can tell whose bets belong to whom. You state a value for your chips when you buy in, and that value stays attached to that colour until you cash out.
Once the dealer clears the previous round and calls for bets, you place chips on the layout. You may place inside bets on individual numbers or small groups, outside bets on red, black, odd, even, high or low, or a combination of both. The dealer spins the wheel in one direction and sends the ball travelling the other way around the outer track. When the ball drops into a pocket, the dealer marks the winning number on the layout and settles every bet.
Losing chips are swept away first. Winning bets are paid next, and the original stake stays on the layout until you collect it or leave it to ride. On an even-money bet, a winning chip pays one unit for every unit staked. On a straight-up single number, the payout is 35 to 1. The payout is always calculated from the winning number only; the green pockets pay nothing on outside bets and are a separate inside bet if you choose to play them.
Bet Types and Where the Edge Sits
Roulette looks like one game, but it is really a collection of separate bets with different odds and different payouts. The house edge is not uniform across the table. Some bets return more of the wagered money over a very large number of spins; others return less. The differences are small but real, and they accumulate with every spin.
| Bet type | Pockets covered | Payout | What changes the edge |
|---|---|---|---|
| Red or black | 18 | 1 to 1 | Green pockets lose; American wheel adds a second losing pocket |
| Odd or even | 18 | 1 to 1 | Same as colour bets; zero is not odd or even on most layouts |
| High or low | 18 | 1 to 1 | Same structure; zero sits outside both ranges |
| Straight up | 1 | 35 to 1 | Payout below the true odds; edge is built into the payout |
| Split | 2 | 17 to 1 | Same principle; edge comes from the shortfall against true odds |
| Street | 3 | 11 to 1 | Edge differs by wheel type but not by the numbers chosen |
The table above shows the structural difference. Outside bets lose only to the green pockets, so their edge is entirely a function of how many zeros the wheel carries. Inside bets are priced by payout rather than by the zero alone: a straight-up bet pays 35 to 1 when the true odds against hitting one number are 36 to 1 on a European wheel and 37 to 1 on an American wheel. The shortfall between the payout and the true odds is the house edge on that bet. No bet on the layout escapes it.
What a Strategy Chart Does and Does Not Do
Roulette does not have a basic-strategy chart in the way blackjack does, because the player makes no decisions after the ball is released. The only decisions are which bets to place and how much to stake. What does exist is a set of published reference tables showing the expected loss per bet type under a given wheel configuration. Those tables derive from the exact rule set in use: how many zeros, what the payout schedule is, and whether any special rules apply, such as a rule that returns half a losing even-money bet when the zero lands.
Any chart you consult is only as good as its match to the wheel in front of you. A table built for a single-zero wheel understates the edge on a double-zero wheel. A chart that assumes a particular payout schedule is wrong for a table that pays differently. Read the wheel first, then read the chart. If the two do not match, the wheel is the source of truth.
Procedural Mistakes New Players Make
The first mistake is treating roulette chips like cash at the table. They are not. You cannot pocket them and take them to another table. You must cash them out at the roulette table where you bought them, because their value exists only in the dealer's record of your colour. Walking away with them means walking away with clay discs that have no value anywhere else.
The second mistake is placing a bet after the dealer has called no more bets. Once the call is made, any chip that lands on the layout is late, and the dealer will either return it or treat it as void depending on the house procedure. The moment to act is before the call, not during the spin. A late bet is not a clever edge; it is a breach of the table routine and it will be handled as one.
The third mistake is assuming that the previous spins tell you anything about the next one. A wheel that has landed red five times in a row has not become more likely to land black. Each spin is an independent event, and the wheel has no memory. The red and black counts stay fixed at 18 each, and the green pockets stay green. What changes from spin to spin is only the outcome, not the odds.
FAQ
Do the red and black numbers alternate around the wheel?
They are arranged so that no two consecutive numbers share a colour for most of the wheel, but the sequence is fixed and specific to each wheel type. The alternation is a design feature, not a random pattern, and it does not affect the odds on any bet.
Is the zero counted as red or black on any wheel?
No. The zero and double zero are green on both European and American layouts. They are excluded from red, black, odd, even, high and low bets, which is precisely why they create the house edge on those wagers.
Does the number of red and black numbers change between online and live roulette?
The colour count is the same: 18 red and 18 black. What can differ is the wheel type, and therefore the number of green pockets. Check the game information panel or the table rules to see whether the wheel has one zero or two before you bet.
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