The European and American roulette wheels look identical at first glance, but one difference changes the entire game: the American wheel has an extra zero pocket (00), which nearly doubles the house edge.
This guide explains the layout of each wheel, the full number sequence, why the numbers are arranged out of order, and how wheel design affects the house edge.
How Many Numbers Are on a Roulette Wheel?
A European roulette wheel has 37 numbers (0 through 36). An American roulette wheel has 38 numbers (0 through 36, plus 00).
On both wheels, the 36 numbered pockets are split equally between 18 red and 18 black. The zero and double zero pockets are always green.
European vs American vs French Roulette Wheel
The three main roulette wheel variants differ in the number of zero pockets and the rules that apply when the ball lands on zero.
| European | American | French | |
|---|---|---|---|
| Pockets | 37 | 38 | 37 |
| Zeros | Single (0) | Double (0,00) | Single (0) |
| House Edge | 2.7% | 5.26% | 1.35% |
| Special Rules | - | - | La Partage / En Prison |
*On even-money bets with La Partage or En Prison in play.
European roulette wheel
The European wheel is the standard format used in most online casinos and in European land-based casinos.
With a single zero and a house edge of 2.7%, it offers better odds than the American version. The 36 numbered pockets alternate red and black around the wheel; the zero sits in its own green pocket.
American Roulette Wheel
The American wheel adds a double-zero (00) pocket, raising the house edge to 5.26%, nearly double that of the European wheel. Most US land-based casinos use the American format.
The extra pocket also changes the number sequence entirely; the two wheels share no common arrangement beyond the colours.
French Roulette Wheel
The French roulette wheel is physically identical to the European wheel: 37 pockets, single zero, same number sequence. The difference is in the rules.
La Partage returns half your stake if the ball lands on zero during an even-money bet. En Prison keeps your bet on the table for the next spin under the same condition.
Either rule effectively halves the house edge on even-money bets to 1.35%, making French roulette the best option for the player.
The Full Number Sequence on Each Roulette Wheel
The numbers on a roulette wheel do not follow arithmetic order. The sequence on each wheel is deliberately engineered to distribute values, colours, and odd/even numbers as evenly as possible around the circumference.
European roulette wheel – clockwise from 0
0, 32, 15, 19, 4, 21, 2, 25, 17, 34, 6, 27, 13, 36, 11, 30, 8, 23, 10, 5, 24, 16, 33, 1, 20, 14, 31, 9, 22, 18, 29, 7, 28, 12, 35, 3, 26
American roulette wheel – clockwise from 0
0, 28, 9, 26, 30, 11, 7, 20, 32, 17, 5, 22, 34, 15, 3, 24, 36, 13, 1, 00, 27, 10, 25, 29, 12, 8, 19, 31, 18, 6, 21, 33, 16, 4, 23, 35, 14, 2
Why Are Roulette Wheel Numbers Not in Order?
The roulette wheel number layout follows four design rules. Together, they make the wheel as balanced as possible in theory while making it harder for players to visualise sectors or detect bias.
Colour alternation
No two adjacent pockets share the same colour. Every number on the wheel is flanked by two numbers of a different colour. This rule applies without exception to both wheel types.
High/low alternation
Low numbers (1-18) and high numbers (19-36) must alternate around the wheel as consistently as possible.
The European wheel achieves this more cleanly than the American: the only breaks in the pattern are 5 next to 10, and 26 next to 32 (the latter separated by the zero).
The American wheel has multiple sectors where low and high numbers cluster together.
Odd/even distribution
No more than two odd or two even numbers may sit adjacent to each other anywhere on the wheel.
Sector disorientation
The non-sequential layout makes it hard for players to build a mental picture of where specific numbers sit relative to each other. This complicates any attempt to identify bias or bet systematically on wheel sectors, particularly for less experienced players.
Two notable asymmetries on the European wheel
Split the European wheel into two halves, starting from zero. The left half contains all black low numbers and all red high numbers; the right half contains all black high numbers and all red low numbers.
In the nine-number sector 29-7-28-12-35-3-26-0-32, none of the numbers belong to the second dozen (13-24). This creates an asymmetry that affects strategies combining dozen bets with wheel sector bets.
Anatomy of a Roulette Wheel
A roulette wheel is a precision instrument. Any deviation from its construction standards (through wear or deliberate manipulation) creates a biased wheel that advantage players can, in principle, exploit.
Structural requirements
Weight must be distributed evenly across the entire wheel. The cylinder must spin freely, and all other components must remain fixed. Neither the wheel nor the ball may contain magnetic materials. Every pocket must have identical dimensions and spacing, and the ball must be able to settle in any pocket cleanly.
Ball deflectors
Between the ball track and the numbered pockets, there are typically 8 to 16 deflectors, also called diamonds or canoe stops. When the ball leaves the track, it strikes one or more deflectors, altering its speed and direction before dropping into a pocket. Deflectors increase randomness and make trajectory prediction harder.
Frets and pocket design
Frets are the metal separators between pockets. Their height and shape determine how much the ball scatters on landing.
Tall, even frets keep the ball in the first pocket it enters. Low frets cause erratic bouncing across several pockets before the ball settles, producing wider scatter.
Sloped frets (declining toward the centre) were common on early wheels and behave similarly to low frets. Curved frets allow the ball to move between pockets without visible bouncing.
The scatter is real, but players don't see the jumps. Shallow pocket pads, a more recent development, increase scatter regardless of fret type.
Deceleration
As a wheel ages, the ball track degrades, and the ball loses speed faster. This affects where the ball tends to land and is one reason some advantage players prefer older equipment.
Modern manufacturers design wheels to resist deceleration. In online roulette, this is not a factor because the wheel is software.
European Wheel Call Bets: Voisins, Tiers and Orphelins
Some bets are defined by position on the European wheel rather than on the table layout.
In land-based casinos, these are announced verbally to the dealer. Every chip in the bet must be of equal value.
Live Dealer vs Online (RNG) Roulette Wheels
In a live dealer game, a real physical wheel is used, built to the same manufacturing standards as a land-based casino wheel, operated by a croupier, and streamed in real time.
The live roulette experience replicates the physical game as closely as possible, including the unpredictability introduced by deflectors, fret design, and ball material.
RNG (Random Number Generator) roulette uses software to simulate the wheel. Each spin is determined by a certified random number generator, independently audited to ensure outcomes are statistically equivalent to a physical wheel.
There are no deflectors, no ball materials, no deceleration, just a mathematically verified random result. Licensed operators are required to use certified RNG software, so concerns about rigged outcomes do not apply to regulated online casinos.
Both formats offer the same bets, the same payouts, and the same house edge for a given wheel variant.
Roulette Wheel Manufacturers
Three manufacturers dominate the professional roulette wheel market:
- Cammegh, based in Ashford, Kent, is an independent manufacturer and one of the market leaders.
- TCS John Huxley (formerly John Huxley, acquired by TCS) is known for the Starburst wheel design.
- Paul-Son, acquired by Gaming Partners, completes the major three.
It’s possible to combine components from different manufacturers on the same wheel.
One notable development from Cammegh is Random Rotor Speed (RRS) technology on the Mercury 360 wheel.
RRS uses a contactless mechanism to vary the rotor's speed during play, disrupting techniques used by advantage players, including roulette computers and dealer signature exploitation.
Some casinos using RRS-equipped wheels have reportedly had them fitted with TCS John Huxley turrets, concealing the technology in use.
FAQ – Roulette Wheel Numbers
How many numbers are on a roulette wheel?
A European wheel has 37 numbers (0-36). An American wheel has 38 (0-36 plus 00).
What is the highest number on a roulette wheel?
36 is the highest number on both European and American roulette wheels.
How many red and black numbers are on a roulette wheel?
Both wheels have 18 red and 18 black numbered pockets. The zero (and double zero on American wheels) is green.
Which roulette wheel has the best odds?
French roulette with the La Partage rule offers the best odds, with a house edge of 1.35% on even-money bets. The European wheel is the next best at 2.7%. The American wheel, at 5.26%, is the least favourable for the player.
What is the difference between a European and American roulette wheel?
The American wheel adds a double zero (00) pocket. That single extra pocket nearly doubles the house edge, from 2.7% to 5.26%, and changes the entire number sequence.
Are online roulette wheels random?
Licensed online roulette uses certified RNG software audited by independent testing labs. Each spin is statistically random and independent of all previous spins.
Key Takeaways
- A European roulette wheel has 37 numbers (0-36); an American wheel has 38 (adding 00); a French wheel shares the European layout but adds La Partage or En Prison rules.
- The house edge is 2.7% on the European wheel, 5.26% on the American, and 1.35% on French roulette with La Partage on even-money bets.
- Roulette wheel numbers are arranged out of arithmetic order by design, following rules for colour alternation, high/low balance, odd/even distribution, and sector disorientation.
- Call bets (Voisins du Zéro, Tiers, Orphelins, Jeu Zéro) are referenced by position on the European wheel, not the table layout.
- Fret height, pocket design, and ball material affect how much the ball scatters. Tall frets mean less scatter, low or curved frets mean more.
- A regulation wheel must be evenly weighted, non-magnetic, and built to identical pocket specifications. Deviation creates a biased wheel.
- Live dealer roulette uses a physical wheel; RNG roulette uses certified software. Both offer the same house edge for a given variant.
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