Roulette rules connect a marked selection with a wheel result. A numbered pocket determines which selections win after each spin. Before calculating anything, identify the wheel and the exact settlement rules. The free demonstration on this site uses ordinary European and American pocket sets with clearly stated payouts.
Roulette rules for the two wheel sets
European roulette has a single zero alongside the numbers one to 36, for 37 pockets overall. American roulette includes another pocket labelled double zero, giving 38. The zero labels are separate outcomes, even though neither qualifies for ordinary odd, even, red, or black selections. Our simulator chooses every available pocket with equal probability. A real table’s published rules may include provisions that the demonstration does not model, so a wheel label alone is not a complete description.
Recognise the supported groups
Red and black each cover eighteen numbered pockets. Odd and even each cover eighteen. Low covers one through eighteen, and high covers nineteen through 36. A single-number selection covers only its named pocket, including zero when selected directly. Other layouts can offer split, street, corner, dozen, or column selections. Those are outside the supported simulator controls. Do not assume a missing control has been silently included when interpreting the tool result.
Calculate the payment without double counting
An ordinary straight-up award is stated as 35 to one in net profit. A five-credit successful selection on pocket fourteen therefore earns 175 credits of profit, with a gross return of 180 credits after including the original five. An ordinary even-money selection earns five credits of profit at that stake, giving ten gross. Losing either selection costs its five-credit stake. These distinctions explain why payout wording must say whether the original stake is included.
Zero changes the probability
The numbered colour groups still cover eighteen pockets even when the wheel has 37 or 38 available results. Zero therefore prevents red and black from being equally likely halves of the complete outcome set. Under our ordinary rules, zero loses both colour selections. There is no half-loss refund or held stake. Earlier outcomes do not create a balancing requirement for the next independent spin. Use the odds calculator to compare the denominators directly, and use the simulator only to observe settlement under the selected assumptions.
Common questions
Can zero win a red selection?
No. It wins only a selection that actually covers zero under the relevant rules.
Does an American wheel pay more for a straight selection?
The standard straight-up payout remains 35 to one in this model.