Roulette section

ck666 Roulette: wheels and layouts

One ball's stopping place gives a number that can also belong to colours and groups. The first distinction in ck666's roulette subjects is the wheel: single zero and double zero do not share the same outcome space.

One wheel
One ball
Number layout
Table groups
European format Single zero
Compare dice A different structure

Separate the wheel's outcome from conditions on the table. Pocket order around the wheel is not the same as the rows of the layout.

Produces the outcome
Layout
Maps the conditions1–36
Ordinary numbers0
A separate pocket00
American distinctionInside
Number conditionsOutside
Broader groupsVersions
European
One 0
Pockets
37
American
0 and 00
Usual pockets
38

Look at the structure, beyond the name

Both wheels share ordinary numbers, but the number of zeros changes the outcome space. Pocket structure matters more than the colour scheme of an illustration.

European wheel

Numbers 1 to 36 plus one 0 form the conventional European wheel. A selected single number has a 1/37 chance on a fair wheel.

American wheel

An additional 00 distinguishes the conventional American wheel. A selected single number then has a 1/38 chance.

Pocket order

Neighbouring pockets are not equivalent to adjacent numbers on the layout. Wheel positions and table groups are arranged differently.

Colour results

Zero is outside the ordinary red and black groups. Two colour names do not make each colour exactly half of all outcomes.

Grouped results

Odd/even and low/high divide the ordinary numbers. Zero has a separate role.

Special versions

Some tables may include special provisions for zero. Do not infer those provisions from the format's name.

What the layout markings mean

Smaller inside groups and broader outside groups cover different numbers of outcomes. Identify what a condition includes before interpreting it.

Inside groups
Number-based
Single number

Only one selected number matches. Another pocket does not satisfy that single-number condition.

Split
Two numbers

A conventional split covers two adjacent layout numbers, identified by the shared line.

Street
Three numbers

A three-number row on the layout need not be a group of neighbours on the wheel.

Corner
Four numbers

The shared corner identifies four layout numbers. Check which numbers are included.

Outside groups
Broader coverage
Dozens

1–12, 13–24 and 25–36 form separate dozens. This is different from the two low/high halves.

Columns
Vertical arrangement

A column's twelve numbers are not twelve consecutive numbers.

Colours
Red and black

Zero lies outside both ordinary colour groups. Two labels do not imply an exact half chance.

One outcome, several descriptionsFrom number to groupCheck the coverage

The result 8 is black, even and low on a conventional layout.

The result 19 is high and belongs to the second dozen.

A dozen and a column each cover twelve numbers but are different sets.

Choosing broader coverage does not guarantee profit.

A payout figure is not a probability figure.

Read any special provision for zero separately.

Group comparison
Name Example
Coverage Single
8 One number
Street 7–8–9
Three numbers Dozen
1–12 Twelve numbers
Low 1–18
Eighteen numbers Zero

Five examples that prevent mistaken matches

Changing the question asked about a result changes the answer. These examples distinguish related but separate descriptions.

Result 8

Eight is a specific number and also belongs to the low group.

Number
Direct outcome Also a group
Result 19

Nineteen is high and in the second dozen. High does not mean third dozen.

Boundary
Two halves Dozens differ
Result 0

Do not include zero in the ordinary even or low groups.

Zero
Separate rule Outside colours
Adjacent pockets

Wheel neighbours need not form a street on the table layout.

Position
Wheel and table Different structures
Result history

Earlier black results do not make red compulsory in the next round.

Independence
Previous rounds No guarantee

The relationship between wheel and layout

The roulette outcome is one pocket. The layout provides ways to match that result with different conditions. Separating those roles makes the explanations easier to follow.

Why zero is central to the comparison

Consider numbers 1–36 plus a single 0. The ordinary red and black groups divide the 36 numbered outcomes, rather than splitting all 37 outcomes equally. That extra pocket changes the simple assumption that two colours imply equal halves.

Adding 00 on a conventional American wheel increases the outcome space again. A similar-looking payout does not make the mathematical structure identical. Special table provisions must be considered separately from this general comparison.

Several descriptions of one result

If the result is 8, the answer to a single-number question is eight. The same result can also be described as even, black and low. These matching descriptions do not create additional information about the next round.

For a new reader, it helps to identify the number first, then its groups and finally the exception for zero. Continue to the single-zero detail for specific rules, and do not treat the history of results as a guarantee.

ck666

European roulette

Dice

Questions about the roulette section

Identify the structural difference first, then open the detail page for a particular rule or calculation.

The single-zero detail explains a selected number's probability and a payout example.European detailsNames alone do not specify every condition.

Does each colour have a half chance?
No. Zero is outside the ordinary colour groups.
Is zero an odd result?
It is not included in the ordinary odd/even outside conditions.
Where is 00 used?
It is a separate pocket on the conventional American wheel.
Is pocket order the same as layout order?
No. They are arranged differently for different purposes.
Is a dozen the same as low/high?
No. A dozen covers twelve ordinary numbers; each half covers eighteen.
Which page should I read next?
European roulette provides specific single-zero examples.

Continue to a specific set of rules

After the basic wheel comparison, read about single-zero roulette or compare its structure with dice.

European roulette Dice section Help