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What Is A Provably Fair Bitcoin Casino? Simplified.

You probably are aware of Bitcoin by now and possibly even aware of it's amazing benefits when it comes to gambling at a Bitcoin casino which can offer very low house edges, both very high betting maximums and low minimums while offering fast and safe deposits and withdrawals. But those are just some of the initial benefits to playing on a Bitcoin casino. A select few additional Bitcoin gambling sites around the web also really care about their games' integrity. It's one thing for a casino to state that they have a fair gambling game and that it's users should simply trust you. It's a slightly better thing when that gambling code has been third party audited for fairness. But even then, you have to trust the third party auditor and also hope that the gambling company didn't alter their random number generator (RNG) after the audit to manipulate the results.

Provably Fair: The Ultimate Solution

Ever since there has been a transition away from mechanical styled casino games and over into the digital era of computerized machines, the inherent level of trust must grow between the operator and the consumer. Because who is to say any arbitrary digital result is fair? And yet, through many discovered acts of online casino maliciousness, there can often be an erosion of overall consumer confidence in the online gambling sector. With some simple internet searches, you can find plenty of examples where users won massive slot machine jackpots or other such prizes and weren't paid out in the end. And of the payouts that do occur, how can the user even know if their end result is fair? They simply can't. They just have to trust in the system. The problem with this kind of logic is that by placing your full faith into the system, you open yourself up entirely to exploitation. Because the times the online Bitcoin casinos are being honest you stand to gain nothing. And yet, when they are dishonest, you can really be taken to the cleaners for all of your precious satoshis.


Thus, provably fair Bitcoin gambling has come about as one way to complete the circle of trust between the client and the operator. Through some fancy maths which will be explained below, a user can determine matter of factly that all of the betting that has occurred was in fact fair for them.

How Does A Provably Fair System Work?

There are a few major components that we'll need to explain and describe in some level of detail. And they are:

  • Server Seed
  • User Seed / Client Seed
  • Nonce

These technical words will be capitalized throughout the article for ongoing clarity even if this is not grammatically correct.

The Server Seed is the seed that is controlled by the Bitcoin casino. To generate this, a public hash of the seed is shown - a character string that is easy to show to the public without revealing the private key that lies beneath. Very similar to how Bitcoin works with public and private key cryptography. The Server Seed will stay constant with each new generation of events.

The User Seed is the seed that the user or player of the Bitcoin casino controls themselves. This code can be manipulated by the user. Because the user is able to manipulate the code any which way that they want to, this is the essence of how a high integrity Bitcoin casino can ensure that it's games are fair.

The Nonce is a fairly simple term to describe which bet number is taking place in a string of bets.

A Seed Pair is the combination of both the Server Seed and the User Seed.


The way this all works is that for each bet, the present Server Seed and User Seed are combined together and start at Nonce #1. To place a second bet, the same Server Seed and User Seed are combined onto Nonce #2. This process repeats to infinity until the Server Seed and User Seed are changed by the individual Bitcoin gambler.

The magic occurs when a new Server Seed and User Seed are created for two reasons. The first reason, as was previously stated, is because the user may choose their own User Seed. This forces the fact that the seed combination has to be fair since MintDice or any other provably fair Bitcoin Casino has no way of knowing what User Seed the user will pick. The second reason is because when a new Server Seed is generated, the private key to the old Server Seed is released which can show all of the bets along the Nonce of that betting string. Therefore, every single bet that has ever taken place previously can be known to the Bitcoin gambler meanwhile they won't know any future bets because their present Server Seed's private key has not yet been released but is instead held by the house until yet another Server Seed and User Seed combination are created again.

What Does Provably Fair Look Like?

Let's take a look at what a normal provably fair situation may look like for your average Bitcoin gambler. And we'll use the templates from the 100% provably fair Bitcoin Casino, MintDice, as the example provided here:


In this example, we see a standard current Server Seed and Client Seed. It is also shown on public display what the future Server Seed's hash will change to, should the Bitcoin gambler wish to change their current Seed Pair. Once the Seed Pair is changed, the private key to the former Server Seed is revealed as stated earlier and you can then verify your bets. Each website may tackle this problem a little differently. MintDice has an open source Provably Fair Verifier that is available on JSFiddle. This allows you or anyone to inspect the code as well that is used to verify your bets so that you can not only trust that MintDice is using Provably Fair technology but that it is physically out there in the open for anyone to inspect.

As stated earlier, these provably fair tools are semi customizable to your liking. You can skip past various Server Seeds and more importantly, choose your own User Seed / Client Seed based on fairly loose parameters that look like this:


As you'll see, the Server Seed in this picture cannot be edited. The future or present seeds may not be altered. If you've followed along to this point, the private Server Seed is the only thing that separates the Bitcoin gambler between a proper casino game and perfectly knowing all future rolls were they to obtain the Server Seed due to some form of Server Seed leak or hack. This type of hack has happened in the past which has allowed users to take advantage of provably fair casinos. It's for this reason that most casino operators must take security extremely seriously as to not leak Server Seeds to the public.

Importantly, though, the Client Seed is modifiable. And this is one of the most important steps to ensuring a fair game for literally all players of a provably fair Bitcoin casino. You can choose any string of alphanumeric characters so long as it is 30 characters or less. This could be your Grandmother's nickname followed by her favorite lucky numbers or literally anything else you can think of. The luckiest version that we can think of that would be acceptable would look like this:


You'll notice that the fairly cheeky run-good and super lucky Client Seed that we input is acceptable within the parameters and could therefore be used as part of the Seed Pair for anyone that elected to do so as denoted by the green Change Seed Pair button as opposed to the empty red button up previously.

It is our recommendation to always use different customizable client seeds for any provably fair Bitcoin casino that you intend to play on. This completely prevents any malicious Bitcoin casino operator from pretending to be honest with actual malicious intentions. How is this possible? Any casino operator can view all future gambling outcomes on their games. In theory, a Bitcoin gambling operator could then purposefully provide unlucky default Seed Pairs to their users initially. But by choosing your own User Seed, this will with almost 100% certainty thwart this attack vector (unless very strangely the casino was able to predict what User Seed you would end up choosing).

How Is Provably Fair Used By Players?

Most users will simply just accept the initial Seed Pair provided to them by a website. By and large, since most Bitcoin casinos that are offering exclusively provably fair games will be honest, this is more than sufficient. As we just suggested earlier, if you want to be careful, always choose at least partially random Client Seeds for yourself.

From a practical standpoint, some users like to make sure that the provably fair Bitcoin casinos are being honest and will verify the RNG outcomes that they have received over any particular Seed Pair that they have previously used. This helps keep any website honest. Because any provably fair site realizes that it's users may be willing to verify bet outcomes, it would be suicidal to do anything but provide it's players with fully truthful outcomes. Keep in mind, as always, that this feature is physically impossible for all non-provably fair casinos to provide.

Meanwhile a large portion of players prefer to change their Seed Pairs over time to change the course of their otherwise predetermined fate. Once any Seed Pair is in motion, all of the future Nonce values of any Seed Pair are static and cannot be changed. Therefore, the trajectory is fixed. Through certainly gambling superstitions or other forms of "luck-logic" some gamblers may wish to change to a new Seed Pair. The common reasons for this may include:

  • A Seed Pair has been consistently unlucky and a player wishes to change to or find a lucky Seed Pair.
  • A Seed Pair has been consistently lucky and a player wishes to change the Seed Pair to a new one before it's luck runs out due to regression towards the mean logic.
  • Some users like starting each session off with a fresh Seed Pair to have a hard reset at the start of each Bitcoin casino session.

Whatever your reason is, the option exists to either stay the course or change the future of your future gambling outcomes. Yet again, this is another great novelty feature that only exists for players that are playing on a provably fair casino. On any other "normal" online casino (read: Not Provably fair), you are forced to accept all future outcomes of gambling events and have no way of knowing if they were fair and have no way of altering the future reality of these outcomes.


Final Take Away Message About Provably Fair Games

With such a broad array of possibilities on the internet and with so many scammers afoot, particularly in the online casino/gambling and cryptocurrency spaces, you should really only give yourself the best chances to win and you should accept no less. This really pins you down to two major features that very few Bitcoin casinos, let alone casinos in general, offer to the public. And these are looking for a low house edge and games that are provably fair.

Your single best way to beat the house and take home some lucky winnings will be to maximize your chances with low house edge games. It's really your only chance to get math more on your side than otherwise. And typically, you will only find house edges that are very low on Bitcoin casinos which can be as low as only 1-2%. Normal online casinos will have too many costs associated with their operations and will frequently charge you as much as 5-20%. Even if these online casinos are being honest, your chances of coming out ahead as a casino player will really have the odds stacked against you relative to a high quality Bitcoin casino.

The other feature as we've really harped on this entire article deals with Provably Fair games. We live in a world where over 99% of casino games currently in existence are not provably fair. And yet, with the small minority of provably fair games that do exist, why would you ever settle for less? Why would you want to settle for something that could be rigged against you? There's really no reason to open yourself up to exploitation like that. Trust in math and trust in provably fair technology for all of your online casino play to put as many of the odds in your favor as possible.

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