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Rules, bets, odds and systems, checked with math

Roulette explained, number by number

Roulette explained with honest math: the three wheels, every bet, real odds and house edge, plus a free play credit simulator and wheel spinner.

Play the free simulator See every payout

House edge

  • French, la partage1.35%
  • European, single zero2.70%
  • American, double zero5.26%
  • Triple zero7.69%

25 guides and 6 free tools

Roulette is a table game where a dealer sends a small ball around a spinning numbered wheel and players bet on the pocket where it will stop, from one single number to half the board at once. This site walks through the whole game the way a dealer would teach it on a quiet shift: the rules, each place you can put a chip, the real chance of every bet, and what systems do to a bankroll. Every tool here runs on play credits, so you can try anything before you ever sit at a real table.

At the table

  • Pockets

    37 on a European wheel, 38 on an American wheel, 39 on a triple zero wheel
  • Biggest payout

    35 to 1 for one number, so 1 unit comes back as 36
  • House edge

    2.70% with one zero, 5.26% with two, 7.69% with three
  • Cheapest bet

    Even money bets under la partage, about 1.35%
  • Can a system win?

    No. It changes how results are spread, never the edge
  • Free tools

    Simulator, wheel spinner, betting layout, odds and system calculators

What roulette is, in one minute

The name is French for little wheel, and it is said roo-LET. A wooden wheel holds numbered pockets colored red, black and green. Picture two motions fighting each other: the rotor drifts clockwise or counterclockwise, and the ball races the opposite way along a groove just under the rim. When the ball slows, it drops, bounces off small metal bumps, and settles in one pocket. That pocket is the winning number for the round.

Around the wheel sits a felt layout carrying 1 through 36 as a grid of three columns, the zero or zeros at the top, and larger boxes for colors, odd and even, high and low, dozens and columns. You bet by setting chips on that cloth. A chip on one number is the purest bet in the game, which is why a call like "17 black" is so famous: its square lies close to the center of the felt and is easy to reach. It has no better odds than any other number.

For a slower tour of the parts, the words and the history, read what is roulette. To start playing right away, go to how to play roulette.

The three wheels you can meet

Every roulette game uses the same 36 numbers. What changes is the number of green pockets, and that one detail sets the price of every bet you make.

WheelGreen pocketsTotal pocketsEdge on most betsWhere you see it
European0372.70%Across Europe and on many screens
French0372.70%, even money near 1.35%Tables using la partage or en prison
American0 and 00385.26% (top line 7.89%)Standard across US casino floors
Triple zero0, 00 and 000397.69%Some US casinos
If two tables offer the same limits and one has a single zero, pick that one. It cuts the average cost of play roughly in half compared with a double zero wheel.

The order of the pockets differs between wheels too. See the European wheel and the American wheel for the full sequences.

How a round of roulette works

A round takes about a minute at a live table and a few seconds on a screen. The rhythm never changes:

  1. Buy in. Hand cash to the dealer and receive a stack of wheel chips in a color no one else at that table has.
  2. Bet. Place chips on numbers, lines between numbers, or the outside boxes. You can make many bets in one round.
  3. Spin. The wheel turns and the ball is launched against its direction. Chips can still go down for a few seconds.
  4. No more bets. The dealer waves a hand over the layout and calls it. Chips placed after this do not play.
  5. The ball lands. Out comes the dolly, a heavy little marker, set right on that number's square.
  6. Settle. Every losing chip is cleared away, then each winner is paid beside the bet. A winning chip stays yours along with its payout.
  7. Repeat. The dolly comes off and the next round opens.

Rehearse those steps on the free roulette simulator; it opens with 1,000 credits.

Inside and outside bets at a glance

Bets fall into two families. Inside bets sit on the numbered grid and hold between one and six numbers. Outside bets sit in the boxes around the grid and cover twelve or eighteen numbers. Fewer numbers means a rarer win and a larger payout.

  • Inside: straight up, split, street, corner, six line and the zero bets such as the basket.
  • Outside: the color bets, odd against even, low half against high half, and the dozens and columns.
  • Call bets: groups of pockets named by their place on the wheel, explained on call bets.

The one trap for new players is the green pocket. Green belongs to none of the outside groups, so when the ball finds a zero, color, parity, half, dozen and column bets all go down together. Read more on the green 0 and 00.

American roulette layout with chips on a straight up 17, a split, the second dozen and red
Four common bets, from the rarest win to the most frequent.

Roulette odds in one table

Each payout falls short of the fair price by a sliver, and that sliver is the house edge. Here is every standard bet, widest first, with its chance on both main wheels:

Chance per spin, rounded to two decimals
BetPaid at1 unit comes back asSingle zero chanceDouble zero chance
Any color, parity or half1 to 12 units48.65%47.37%
Any dozen, any column2 to 13 units32.43%31.58%
Double street of six5 to 16 units16.22%15.79%
Top line (American only)6 to 17 unitsnone13.16%
Corner, or first four8 to 19 units10.81%10.53%
Street or trio of three11 to 112 units8.11%7.89%
Pair split17 to 118 units5.41%5.26%
Lone number35 to 136 units2.70%2.63%

Want the math behind each line? See payouts and odds for the working, and the probability page covers streaks and long runs.

Bar chart of roulette house edge by wheel type, from French la partage to triple zero
The more green pockets, the more each bet costs on average.

Why roulette always keeps a slice

Take a single zero wheel. A straight up bet has 1 winning pocket and 36 losing ones, so an even trade would return 36 for every 1 risked, yet the dealer hands over only 35. Over 37 bets of 1 unit you would, on average, win once and collect 36 units back, having spent 37. That missing unit, spread over 37 bets, is the 2.70% edge.

The same gap appears on every bet, because all payouts are worked out as if the zeros did not exist. That is why expected loss is simple to estimate: multiply the edge by everything you bet. Bet 1 unit per spin for 200 spins at a European table and the long run average loss is about 5.4 units. Swap to a 00 wheel and the figure roughly doubles to 10.5 units.

No betting system, pattern or prediction trick changes this. Systems only move losses around, trading many small wins for a rare large loss or the reverse. Test any of them on the system pages listed below before you believe a claim, and see how to beat roulette for the full honest answer.

Free tools on this site

Every tool works in the browser, uses play credits or units, stores nothing and needs no account.

ToolUse it toFind it on
Roulette tableBet with play credits on a single zero table; the other game pages carry their own versionsFree roulette simulator
Wheel spinnerSee pocket order and run 100 or 1,000 spins to watch hot and cold counts formSpin the wheel
Interactive layoutTap a bet type and see the payout, chance and edge for both wheelsTable layout
Payout calculatorCombine bets in units and see the return and expected loss per 100 spinsPayout calculator
System testerReplay Martingale, Paroli and other systems across as many as 1,000 sessions and count how many end brokeMartingale

Play: the game, the wheel and the table

Start here if you have never played, or if you want to know exactly what you will see at a table.

GuideWhat it covers
How to playThe full beginner route, from buying in to collecting a win
What is rouletteMeaning of the word, the parts of the game and where it came from
Free roulette simulatorA complete table with 1,000 play credits, no download
Spin the wheelA spinner in true pocket order with 100 and 1,000 spin buttons
Table layoutTap any bet and watch the covered numbers light up
Wheel numbersHow many numbers, which ones are red, and why the order looks scrambled
American rouletteThe double zero game found at most US tables
European rouletteThe single zero game and its lower edge
French rouletteFrench names on the cloth plus the half back rules on zero
Triple zero rouletteThe 39 pocket wheel and why it costs the most
American wheelThe 38 pocket order, with 0 and 00 facing each other
European wheelThe 37 pocket order and how its colors alternate
Roulette chipsColored wheel chips, how their value is set and cashing out
Table limitsMinimums, maximums and how the inside rule differs from the outside one
Roulette in Las VegasWhat to expect at a Nevada table before your first spin
California rouletteWhy some California tables use cards to pick the number

Bets: every place a chip can go

One page per bet, each with a layout picture, the payout, the chance on each wheel and common mistakes.

BetIn short
All roulette betsEvery chip position on one page, with payouts
Inside betsBets on the numbered grid, from one number to six
Outside betsColors, dozens, columns and the other wide bets
Straight up betOne number, the 35 to 1 bet
Split betTwo touching numbers on one chip
Street betA row of three across the grid
Corner betFour numbers that meet at one point
Six line betTwo rows side by side, six numbers
Basket betThe zero bets whose name changes from place to place
Dozens and columnsTwelve numbers at a time, at a 2 to 1 price
Red or blackThe most played bet and what zero does to it
Call betsVoisins, tiers and orphelins, the sections of the wheel
Green 0 and 00What the green pockets are and how to bet on them
Best betsWhich bets cost the least, ranked by edge

Odds: payouts, probability and the edge

The numbers behind the game, worked out step by step.

PageThe question it answers
Payouts and oddsWhat each bet returns and how often it should hit
Payout calculatorAdd your bets in units and see the return and expected loss
Roulette probabilityStreaks, misses and the chance of any outcome
Casino house edgeWhere the edge comes from and what it costs per hour
Casino games with best oddsHow roulette ranks against other table games
Is roulette riggedHow wheels and number generators are tested
Best numbersWhy no number is luckier than another
Roulette predictionWhat past results can and cannot tell you

Strategy: systems tested honestly

Each system page explains the rules, shows a winning run and a losing run in units, and opens the tester with that system loaded.

System or guideWhat you will find
Roulette strategyWhat a plan can control and what it never will
Betting systemsEvery popular progression, side by side
How to beat rouletteThe honest answer, with numbers
Roulette tipsPractical habits that cut the cost of playing
Strategy chartOne chart comparing systems by risk and reward
Small bankrollMaking 100 units last longer
MartingaleDouble after a loss, and where it breaks
FibonacciA slower climb through 1, 1, 2, 3, 5
ParoliPress wins, not losses
LabouchereThe crossing off line system
James Bond strategyThe 20 unit pattern that covers 25 numbers
RomanoskyTwo dozens and two corners, 32 numbers
Whatever you play, pick a loss ceiling and a clock time to leave before the first spin, and walk away at whichever comes first.

Questions players ask

How do you pronounce roulette?

Say roo-LET, with the stress on the second part. The word comes from French and means little wheel.

What are the best roulette tactics?

The tactics that help are about cost, not winning more often. Choose a single zero wheel, use even chance bets at a French table with the half back rule when you find one, and set a stopping point in advance. No tactic turns the house edge in your favor.

Can you win at roulette?

You can win in a single session, since short runs swing both ways. Over many spins the average result moves toward a loss equal to the house edge times the total amount bet. That is true for every bet and every system.

What does 17 black mean in roulette?

It is a straight up bet on the number 17, which is black on the layout. It pays exactly what every other single number pays. It is popular because it sits in the middle of the grid, not because it wins more often.

What is the roulette marker?

It is a small weighted piece, often called the dolly, that the dealer places on the winning number after the ball lands. While it is on the layout, nobody may touch chips. Once winners are paid, it comes off and betting opens again.

Is online roulette real or fake?

Licensed electronic roulette uses either a real wheel on camera or number generating software that outside labs have checked. Gaming regulators, for instance those overseeing Nevada and Britain, insist on that testing. The house edge still applies in exactly the same way.

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