Keno online

Casino Games - Keno

Keno is a lottery with 80 numbered balls that was originally played in ancient China and was brought to the West, specifically to America, in the nineteenth century by Chinese immigrants. Keno is a game that is now commonly found in online casinos. Online keno games differ from traditional Keno in that the maximum number of balls selected is 15 as opposed to the 20 balls which are selected in land based licensed casinos where the physical game is often managed as a state monopoly. 

Rules of Keno

Keno is played as follows: the player selects up to 20 numbers (or 15 for online games) between 1 and 80. The numbers are then marked on a special ticket or card. Then, 20 balls from the possible balls numbered 1 to 80 are drawn from a digital random number generator (RNG), in the case of keno games online, or from a device such as or like a tombola in traditional betting establishments. The aim of this game of chance is to correctly guess the numbers that will randomly be selected; the more balls chosen correctly on a Keno card, the greater the possibility of winning. When filling out the card, the player may notice that the cards themselves indicate the size of the bets and the amount of numbers chosen. This avoids any confusion either during or after numbers have been drawn, particularly in physical casinos in which keno lottery is sometimes carried out so fast that players do not have time to check their numbers. The bet varies depending on the number of rounds. All combinations are random, and no element of skill is involved. However, many players use statistical strategies to 'inform' their bets, that is, they draw upon information regarding the frequency with which balls have been previously called. Online casinos provide these statistics on their keno pages.

Probability – The Odds of Winning

In the world of casinos there is a theory that the house, the betting establishment, has the advantage over players. This is based upon a mathematical expectation, namely, that the odds are always stacked in favor of the casino. Indeed, Keno is one of the least profitable games for casino visitors, with a house advantage typically varying somewhere between 25 to 29%. The probability of hitting the 20 numbers is considered practically impossible. The probability has, in fact, been calculated as a 1 in 3,535,316,142,212,174,336 chance of occurring. However, there are prizes credited to the player's account for as few as two or three successful numbers. The probability is usually calculated based on the number of selected numbers. Therefore, if 20 numbers are selected, the laws of probability would provide an expectation that two to five numbers being matched:

  • The probability of two numbers coinciding is 4.97 %
  • Three numbers - 12.48 %
  • Four numbers - 20.5 %
  • Five numbers - 23.32 %

The odds of drawing five or more numbers are much reduced and there are no reported cases anywhere of a single case in which all 20 numbers have been selected prior to being drawn form a random numbers generator.

Keno Payouts

In Keno there is the concept of a matrix. This is the formula X / Y / Z. The first constant is the maximum number that can be selected in this game. The second is the number of balls that appear. The third is the total number of numbers in the game. European keno often has a matrix of 19/20/80 or 5/20/80.

An online keno screen is very simple, practically all online casino keno games are similar in nature. On screen there is a table or grid with 80 numbers, one number is located in each 'spot'. The player selects the desired numbers before clicking the Start button. The balls fall on screen and any matches are marked with a colour. The table on the screen indicates the payout for the match. As a rule, payouts in online keno are calculated per bet. Typical payouts for the maximum number of selected numbers are as follows:

  • One or two numbers gives zero
  • Three and four provides 0.5 multipliers of the bet
  • Five multiplies the bet by 1
  • Six doubles the bet
  • Seven multiplies the bet by 5
  • Eight by 15
  • Nine by 50
  • Ten by 150
  • Eleven multiplies the bet by 300
  • Twelve by 600
  • Thirteen by 1,200
  • Fourteen by 2,500
  • Fifteen by 10,000

The quick selection option is often available in online keno games. The random numbers generator marks the numbers on the game screen automatically, so all the player has to do is to press the start button.

History of Keno

Many historians consider ancient China as the birthplace of Keno. There are scrolls dating back to the year 200 BC in which the game is mentioned and the idea for the game itself is attributed to an emperor or commander of the Han dynasty of that era. One possible translation of the game's name at that time is 'dove notes'. This name was derived from the practice of revealing the results of the game via the release of white doves. Thanks to the revenue produced by the game, military expenses were able to be paid. It is also said that the Great Wall of China was funded largely from the the income generated by Keno. The keno table contained 120 different symbols. Players selected symbols by marking them with a brush. Special ink was used to make it impossible to change the bet. From this practice, a bet on keno was called 'spot'.

There is an old story that the Emperor of China himself took out keno 'notes' twice a day with different combinations from a box. If a person's symbols matched those of the ruler, the player received a large prize. Keno was very popular among young and old alike. The modern name of the game most likely derives from the French Five, the five winning numbers. But in the West this game became known only in the nineteenth century, when Chinese immigrants arrived in America which was when the original 120 symbols were replaced by the 80 numbers that are used today. At that time the Americans used 20 cardboard boxes with 80 sheets of paper on which the numbers were written. A sheet with a number was selected from each box. Of the 20 sheets the winning combination appeared. Later, the boxes were replaced with wooden balls that had numbers inscribed on their face.

Keno Strategy

Each round is unrelated to any other previous or future round, as the balls are randomly selected for each and every game. However, many players choose one of two strategies:

  • Reverse result of the event - This strategy suggests that players should select balls that have not yet been drawn as eventually they will be drawn
  • Betting on frequently drawn numbers - This strategy advises players to select numbers which have historically been more frequently drawn

Both strategies are not statistically verified and keno uses a random number generator. The limitations of the probability theory state that often three, four or five of the numbers appear together.

The D'Alembert and Martingale Strategies

Both the D'Alembert and Martingale strategy offer the chance to bet by focusing on the results of the previous round either with a strategy of 'direct' or 'regressive progression'. The strategy of direct progression is based on increasing the bet when winning and returning to the initial bet when losing. This tactic is practical in that the player only risks their winnings. The strategy of regressive progression (like Martingale) doubles the size of the bet when losing. If you win you must return to the original bet, the possible payout depending on the size of the bet. The greater the bet, the greater the prize. Therefore, winnings should (eventually) offset losses. The danger of regressive progression is the high risk of losing sums which may grow exponentially with each bet and therefore this strategy should be used with considerable caution.

The Number Series and the Dogon Strategy

The 'number series' is based on a constant combination of numbers which the player, when winning, varies slightly by removing two numbers from the set, when losing the player selects an additional number. This is a playing strategy designed to limit expenditure when winning and increase investment in the game when losing in the hope of increasing the odds of winning and thereby defeating a 'losing streak'. The Dogon Strategy uses the same numbers time and again and the player uses only these numbers without changing the combination in the hope that sooner or later they will produce the desired result. This is often combined with the strategy of direct and regressive progression.

Online Keno Game Developers

In the West, Keno is especially popular in physical playrooms, as a state monopoly. In the East, the game is more commonly known, and most online casinos offer an electronic version. Online keno is not currently offered by all manufacturers in the market, although this certainly may change in future. Currently games are provided by the following gambling industry leaders: 1х2 Gaming, GamesOS, Microgaming and Playtech.


Keno is a game which provides 'the house', the casino. with a considerable advantage over the individual players and is not the game of choice for players who wish to focus their gameplay on a high frequency of wins. However, the attraction of this game is that relatively low value bets may produce comparatively large prizes, just as is the case for online slot machines. In Keno there are no complicated rules and so it is very easy to learn to play and is available in all legal and licensed casinos worldwide. Read more about the advantages to playing keno games free online as well as for real money in fully licensed online casinos.