How do They Test Online Slot Games for Fairness?

How do They Test Online Slot Games for Fairness?

Staff Writer
February 23, 2014

How do they Test Online Slot Games for Fairness

A long series of losing spins when you are playing any slot game, or a very poorly paying slot session will often leave many a slot player wondering if the slot they just lost a bundle on is actually fair, and today we are going to take a look at how slot games are tested for fairness, before and after they have been launched online.

Vigorous Offline Testing

Each of the major online slot game designers, such as Playtech, NetEnt, IGT Interactive and Microgaming design all of their slots in house, and having had many years experience of putting together a varied range of slot games they know the ins and outs of designing them.

Once a new slot game has been designed it then goes through a vigorous beta testing period where tens of millions of simulated slot spins are played through and the results of each set of spins is analyzed to ensure that expected long term payout percentage of each slot has been reached.

When and only when a slot game passes all of the in house checks and double checks will a slot game be released online, and this guarantees that the designer of that slot, the casinos at which the slot game will be launched at and of course the players of that slot, will be offering and accessing a 100% fair and random slot game.

Pre Launched Slot Game Verification

There is a company called TST who have for many years now offered a testing facility where both online and land based slot and casino game designers can send their newly designed games to have them independently tested to ensure they are operating exactly the way that they have been designed.

All of the major and some of the lesser well known online casino game designers have signed up to the services of TST and as such pre launch the games that are about to go live are put through their paces and should TST find the games work just as they should then that game gets passed and a certified fair game certificate is issued.

Do look out for the TST logo which is often adorned to the website of a casino whose games have all been passed and verified as fair and random, for this is another guarantee to players that those games they will find offered at any one casino site play fairly and all work as they have been designed to do!

Ongoing Slot Game Testing

All online casinos available online will be licensed in one of several different licensing jurisdictions, and part of the licensing process for any online casino will involve the casino having to prove beyond any doubt what so ever that their slot games are fair.

This will entail not just a one off type of certification but often a licensing authority will force a casino to continually prove their slot games and in fact all of their other available games are working exactly as they ought to do due to their design.

There are a few companies who now offer casinos a fully independent auditing facility, and once a casino signs up for this audit then each month of the year the casino must supply a complete set of gaming logs for the entire casino operation.

What these third party and completely independent auditing companies will then do is to fully and deeply analyze those supplied gaming logs and will work out the exact payout percentages that each casino game has paid out during the last month.

A certificate is then issued which must be displayed on the casinos website and a player or potential player of that casino site then can review each previously issued certificate to see if the slot and other casino games are reaching their expected long term payout percentages.

Another service offered by the independent casino game auditing companies is an annual audit of the random number generators which control the outcome of each single spin of the slot game reels, this is a long and drawn out audit, however when a casino signs up to it they will be issued with a certificate once and only once the random number generators have passed the audit.

If you have a favorite online casino or are looking around for a new casino site at which to play slot games or any type of casino game then do look out for who it is has independently verified the casino games as fair, and also do look out for the monthly audit certificates as by perusing them all you will soon find out how generous the slot games pay and play at each casino site you come across!

Player Gaming Logs

One final aspect of playing at an online casino that you may find interesting is that many casinos now readily give all of their players access to their own set of gaming logs, and by having access to them at any time of the night or day you can see for yourself just how good or bad your online slot playing session have been.

If any online casino does not give you access to your gaming logs then you should be able to request they send you them however it may take a short while for them to be sent to you, but there should never be a problem sending them to you!


You do not ever want to take a risk that a slot game you are playing online is not designed to payout all of the prizes listed on its pay table, and you will always be demanding a fair chance of winning when playing any slot game online.

So with that in mind we would suggest you stick to playing at casino sites we have reviewed and have listed upon our website for each of them have certified fair slot games and have gone to very great lengths to ensure that all of their available slot games work, play and more importantly pay exactly as they have been designed to do!



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