Roulette results have two characteristics – number and color. The game’s three colors are as well-known as any other gambling prop, providing casinos with a kind of dress code of red, black, and green.
Roulette was designed to guarantee the game’s operator a profit. That’s why the payouts don’t equal the odds of winning. Those tiny fragments of odds shaved away by the game’s paytable make its odds insurmountable. Over any given period, you’ll always lose playing roulette against the casino.
Which color comes up most often in roulette, and how can you use this to develop a roulette betting strategy?
I’ll start my answer to this question by analyzing how often each of the game’s three colors wins.
How Often Does Red Win?
On an American roulette wheel, there are 18 red spaces – 1, 3, 5, 7, 9, 12, 14, 16, 18, 21, 23, 25, 27, 30, 32, 34, and 36. That means 47.4% of all the spaces on the wheel are red. If you bet on red every spin, you’d win 47.4% of the time on average.
A winning bet on red pays even money, 1 to 1. For every $1 you bet, you win $1 back. A successful $10 bet on black wins you an extra $10.
European roulette layouts have the same number of red spaces, but one fewer space overall, so the odds change a bit on even money bets on red. Red spaces make up 48.6% of the board, meaning bets on red should win about 24.3 times per hour, losing about 25.7 times.
That’s $243 in winnings per hour against $257 an hour in losses at $10 per bet. Close to an even money expectation, but still slightly in the casino’s favor. Players betting red on European roulette should expect to lose about $14 an hour.
How Often Does Black Win?
Bets on black or red in roulette are the same bet with a different name. You have as much chance of winning by betting on black as you do by betting on red. Anything else you read is based on superstition and not mathematics.
On an American roulette wheel, there are 18 black spaces – 2, 4, 6, 7, 8, 10, 11, 13, 15, 17, 19, 20, 22, 24, 26, 28, 29, 31, 33, and 35. That means, like red, 47.4% of the spaces on the wheel are black. If you bet on black every spin, you’d win 47.4% of the time on average.
Winning bets on black pay even money, 1 to 1, like bets on red. Again, at 50 outcomes per hour, if you bet on black every time, you’d expect to win on 23.7 spins, for a total of about $237.00. The other 26.3 spins would be losses, to the tune of about $263. You’d expect to lose about $27 an hour.
How Often Does Green Win?
An American roulette wheel has two green spaces, one marked 0 and one marked 00. That means there’s a total of 38 spaces, 0-36 colored black and red, and 0 and 00 colored green.
That means 2.6% of the spaces on the wheel are green. If you bet on one of those spaces, you’d win 2.6% of the time on average.
A winning bet on the single- or double-zero green space pays out at 35 to 1. If you bet $10 and you win, you get $360 back. At 50 outcomes per hour, you’ll only see 1.3 of those $360 wins per hour, after spending $490 in bets to get there. An expected hourly income of $468 against an outlay of $500 isn’t a winning strategy.
That’s statistically about the same as on the American roulette game. It means an expected hourly income of $487.50 against that $500 outlay – still not a winning strategy.
Which Color Comes Up Most Often?
Black or red results are more common than green. In American roulette, there are 36 black or red spaces for every 2 green spaces, meaning a black or red result is 18 times more common than a green one. In European roulette, black or red results are 36 times more common than green.
Before I talk about whether black or red is more common, I’ll start with a discussion about those pesky green roulette slots.
Based on the mathematics of the game, you should see a green space win about once per 50 spins, whether you’re playing on an American or European layout.
To test this out on a micro-scale, I pointed my browser to an American-facing casino site that allows play-money bets. I was given fake funds of $5,000 and the choice of an American or European roulette wheel.
I gave the American wheel a whirl first. I placed a $10 chip on the green 0 space and let it ride for 50 spins. It took me 34 spins to get a green space at all, and it was 00.
No win for me, but partial proof of concept. The next 16 spins were unremarkable, showing just how much variance roulette offers in the short term.
I didn’t get a win in my 50 spins on American roulette (even though a green space did come up) but maybe my luck would be better with the European version. Surprise, surprise, it worked. It took me 46 spins, but I did hit a $360 win on the green 0 space.
It cost me $460 to get there, meaning I was in the hole even after a very improbable victory, which demonstrates the problem with a “bet on green every time” strategy.
So, which is more common – black or red? Most gamblers, particularly roulette players, have a preference. This is based on nothing at all, usually, just personal taste. Is there any mathematical basis for the preference for one color over another? Or is there any notable way to find a roulette wheel showing a bias today?
Over the short term, wheels may seem like they show a preference for one color over another. Short-term results are misleading when you’re talking about games designed to be played millions of times throughout their use.
Still, just to see what a player may see in terms of black vs. red outcomes, I ran another simulation, this time running an American and European roulette wheel through 100 results each.
American Roulette Wheel Simulation
I decided to place a standard $10 bet on black for 100 outcomes. Through the first ten results, you’d think betting on black was a secret can’t-lose tactic. Eight of the first ten outcomes were black, putting me up by $60.
Of course, things evened out over time, and by the end of 100 spins, we had 49 black, 48 red, and three green results. After 100 $10 bets on black, I’d won $490 and lost $510.
European Roulette Wheel Simulation
After 10 spins on the European wheel, you could already see a trend developing. I saw two green outcomes, which was a little more than you’d expect, but the other eight were split evenly between black and red.
After 90 more spins, I ended with 47 black, 49 red, and 4 green results. My bets on black led to $470 in winnings and $530 in losses.
Our Final Thoughts
You can’t beat the house at roulette by blindly backing any of the game’s three colors.
But, to keep your betting simple, and just for the sake of entertainment, there’s no harm in backing either black or red and playing roulette all night at its famously stately pace. Expected hourly losses for even money bets in roulette make the game cheaper by the hour than seeing a movie or racing go-karts.
If betting on black or red keeps the night entertaining, go ahead and bet that way. Over the short term, you might even turn a profit.