How the roulette wheel changed, and what stayed fixed
The roulette wheel looks like an object that has never changed, and in the ways that matter to the player it has not: 37 or 38 pockets, the same number order, the same payouts. Underneath, it has been redesigned several times, mostly to stop people doing what the famous-stories page describes. Here is the sequence.
The Paris wheel, 1790s
Thirty-six numbers plus a zero and a double zero. The order of the numbers was not yet standardised. The frets between pockets were high, which made the ball settle quickly and predictably once it dropped. The house took two pockets in 38, the same 5.26% as a modern American wheel.
The American wheel and the eagle
Wheels in the United States in the early 19th century sometimes carried a third house pocket marked with an eagle, giving 39 positions. It was unpopular and gone by the 1880s, leaving the familiar 0 and 00 opposite each other with consecutive numbers placed across the wheel from one another.
The Blanc wheel, 1843
François and Louis Blanc removed the double zero at Bad Homburg. Thirty-seven pockets, one green. The number order that European wheels still use was standardised around this period: 0, 32, 15, 19, 4, 21 and on round, alternating colours, spreading high and low, mixing odd and even so that no arc of the wheel favours any outside bet.
Precision engineering, 20th century
After Jaggers and his successors, manufacturers built wheels that could be levelled precisely, with pockets machined to identical depth and rotors that could be swapped between bowls. Casinos began logging results and rotating wheels between tables. The aim was simple: no pocket should ever be measurably more likely than another.
Low frets and deflectors
Two changes aimed at the timing teams. Low-profile frets let the ball bounce further after it lands on the rotor, scattering the final pocket. Additional and irregularly placed deflector diamonds on the bowl make the drop point less predictable. Together they ended the practical usefulness of ball-timing by the 1990s on properly maintained wheels.
The betting-shop terminal, 2001
Fixed-odds betting terminals put a video roulette wheel in UK bookmakers: a European wheel, 20p chips, a recorded croupier voice, results from an RNG rather than a ball. For most British players this was the most familiar roulette wheel for nearly two decades, until stake limits in 2019.
The RNG wheel
Online roulette's standard form is a wheel that does not exist. A random number generator produces a result from 0 to 36 and an animation displays it. There is nothing to level, nothing to time, nothing to bias. Testing labs check the distribution over millions of spins instead of a mechanic checking a bowl with a spirit level.
The studio wheel
Live-dealer roulette brought the physical wheel back, now with cameras over it, sensors or optical readers to call the result, logged outcomes, and maintenance schedules. It is the Blanc wheel with a hundred years of anti-bias engineering, filmed. The number order is the one fixed in the 1840s.
What stayed fixed
The pocket count on each type of wheel. The number order. The payouts. The green pocket as the house's share. Two centuries of redesign have all been aimed at one thing: making sure the wheel is exactly as random as it was always supposed to be.
Questions and answers
Why are roulette numbers in that order?
The European order was fixed in the 19th century so that red and black alternate, high and low numbers are spread around the rim, and odd and even are mixed. It has not changed since, and every European wheel uses it.
What is an eagle pocket?
An extra house pocket on some early American wheels, marked with an eagle, in addition to 0 and 00. It gave the house three pockets in 39 and disappeared by the late 19th century.