Bitcoin Forum

Provably Fair
Provably fair gambling is a process whereby a player can verify that the outcomes of games have been fair in real time.

It makes use of these three technology:
Random Number Generators

• Random number generators generate millions of numbers per second and determine game outcomes.

Seed Generators

• Seed generators create the numbers which are fed into algorithms, which in turn determine outcomes. In provably fair systems, players get to add a seed number, ensuring the casino isn’t in control of the outcome.

Hashing

• Hashing is the transformation of a longer string of data into a shorter string. In the context of provably fair gambling, when a seed number is hashed, it is encrypted. For all practical purposes, the cryptographic hashes used at Bitcoin gambling sites are considered unbreakable. This means you can be sure they haven’t been tampered with.

How does provably fair work?
Although there are several implementations of the provably fair method, we will describe the most common one. With this method each roll-result is calculated by the following variables:

Serverseed - provided by the gambling site

• You will get an encrypted hash of the serverseed before you start gambling. Since you get it in advance, the site cannot change it later. However it is encrypted, so you cannot calculate your own roll results in advance (only afterwards if you get the unhashed serverseed.)

Clientseed - provided by your browser and adjusted by you

• Your browser will generate a random clientseed. However, you could and should adjust this clientseed before you start. This way you can make sure the site does not know your clientseed in advance.

Nonce - A number that increases with each bet you make

• Now if you make a bet the nonce starts with 0 or 1 depending on the website. After each bet you make, the nonce number will go up by 1.

How do you know if a Bitcoin Gambling is Provably Fair?

The easiest way is to use provably fair verifiers.
Here Are the list:
BetKing verifier (https://dicesites.com/betking/verifier)
BetterBets verifier (https://dicesites.com/betterbets/verifier)
BitDice.me verifier (https://dicesites.com/bitdiceme/verifier)
Bitsler verifier (https://dicesites.com/bitsler/verifier)
Crypto-Games.net verifier (https://dicesites.com/crypto-games/verifier)
Just-Dice.com verifier (https://dicesites.com/justdice/verifier)
Nitrogen Dice verifier (https://dicesites.com/nitrogendice/verifier)
Primedice verifier (https://dicesites.com/primedice/verifier)
SafeDice verifier (https://dicesites.com/safedice/verifier)

https://qolczpnfu7-flywheel.netdna-ssl.com/wp-content/uploads/2014/09/provably-fair-gambling.jpg

Provably Fair (https://dicesites.com/provably-fair)
Provably Fair Gaming (https://www.legitgamblingsites.com/bitcoin/provably-fair/)

Most trusted gambling site use provably fair system, for players to verify each bet if it is rigged or not. Thank you for posting a complete and comprehensible definition of provably fair system in gambling. The links will be useful for gamblers to verify if a site uses the system in their platform. Thanks for sharing the links OP.

This is a detailed explanation of provably fair and this is helpful for new online gamblers.
Gamblers prefer gambling sites that has provably fair system. It builds confidence and builds trust to users.
 

The problem with it is that people do not usually check if its actually provably fair or not because it can be quite complicated, various casinos were found to be cheating even though they were using provably fair systems, in theory.

I have to agree that not all gamblers use the system to check their bets. I'm not quite sure why but it seems something related to "trust", once gamblers trust the site then they wont really care about their bets no matter win or lose. The other reason could be about knowledge, maybe some gamblers does not even aware how provably fair system works so they do not care about it so their main idea is to gamble only without worrying about being cheated if they play on non provably fair sites.

I agree, even I sometimes do not verify my bet when gambling  ;D Not because I don't want to, maybe because of trust and sometimes it's tiring to check your bets from time to time. When I was new in gambling I don't really care about this as long as I am playing. ;D

Is there a way for the gambling site to perform a "Man in the middle" attack to hijack the process and to push a simulated version of this process? They provide some in-house tool with exploits to verify the bet, but they game the outcome of the verification process by intercepting the outcome of the output and replacing it with their own doctored result?

Can we trust the in-house verification software that are provided by the gambling site or is there another site where this can be double checked? 

Of course we don't check every time whether the outcome was fair or not. What is important is that we can do that any time we want.  I just did it for my few last bets on PrimeDice, and below are the results:

https://i.imgur.com/JUfUSLY.png

^^These were my bets

https://i.imgur.com/Ms9F7Bx.png

^^ And these are the results of verification from the site dicesites.com/.

It appears that I made 78,868 bets with the previous pair. That's how much I trust PD. :)

That's usually happens with new casinos that promise to offer people all kind of new features just to attract clients. Of course it's always good to verify your bets from time to time, regardless on what casino you are playing but big and trusted casinos would never try to cheat on their users unless they've suddenly decided to turn themselves into scammers.

Provably Fair is the key feature of almost all of the trusted casinos out there. Op did a great job with this guide on the trust system inside a Casino. This is Going to be very useful information for all the newbies out there who do not understand how a casino can be trusted I have seen a lot of people blaming the casino for their bad luck.

Thank you for the details information about provably fair.
To be honest, I never think about provably fair, and so far, I am playing gambling without searching of provably fair or not because I see that almost gambling site have provably fair in their site.
So I think that for me, I only need to play, enjoy the games, spend some money, it doesn't matter if I win or lose.

Some question like even the site A also provably fair, but why they are not success with site B
There are some factor that affect on the site's reputation like community feedback become essential !

So for real situation, why people choose PD over 999dice

Just make sure to note that provably fair is only as fair as the way you test it. If the test is done on the site that you're working with, the site may fraudulently state that everything is fair and legitimate -- but when you go test it on your own independent testing, it says that something is wrong.

So if you are going to be testing bets, don't do it on the site itself -- do it independently.

I'm very much  surprise why Betking is there on the list. I guess its fair despite what the owner of  the casino does. Its always been the dice that is being checked to be fair. There are more casinos that isn't listed in the first post, I don't see their verifier page so is there a way to find out?  Can you check  EOSbet.io?

Well most of them provides the code on how they generate the seeds and generate the outcome. If you are a programmer then you can build a verifier page to verify bets yourself. If they are not releasing their codes then it means that they don't want the players to know about it which makes them look suspicious.

But most players don't even verify that it is provably fair, they just read that the casino says it is provably fair and take their word for it.  There are many ways to deceive players into thinking a game is provably fair and not showing the true odds of winning.

Very interesting post,OP.I've forgotten about how the "Probably fair" mechanism works,because I'm not playing dice and crash games since 2015.

I dont really mind too much on verifying my bets as long i do play on reputable sites because you can already presume that they are fair where such big community already trusted them. Period. Appreciate OP's effort though.

But if you presume all of these are fair, and the site takes advantage of your once or twice you're never going to notice. I would rather waste my time and check all my bets, rather than go through hundrends of bets and get fucked once -- because I was complicit.

I would never just assume all is fair because you're on a reputable website. That's when you'd least expect it tbh.

This is very useful for a fairly new site by implementing a proven system of justice, because most people want it to make the game more comfortable and safe, but will it be used very well and not vulnerable to manipulation? I'm not sure about that because fraud will continue, so I only recommend that the leading gambling sites are very many people who believe in large sites, but that can be tried first to measure its superiority.

They can only deceive people for those who don't know anything about gambling or just playing for pleasure, but those who think gambling will be their source of income will look into it all the time. That is our right to know and to be treated well but somehow, some gambling sites never think about and it causes gamblers never to use their services instead of finding another one.

So that's what it means  ;D

I've been wondering why it's "v" but never really bothered looking for the reason why.

Normally, the site where you test fairness is a third-party one. But, I agree that we can't know for sure whether it is not actually connected to the site we are playing on. The good news is that we can indeed do the test independently, those sites are there just for our convenience, just like Bitcoin mining profitability calculator and similar things.

Knowing the hash of the server seed we can easily check whether it was tampered or not. And then, knowing the client seed and the server seed(unhashed) and applying an algorithm, we can check by ourselves what should the outcome of the roll (or the outcomes of all rolls with the current pair) really be.

Well you do have a point and this do really matter on an individual on how keen you are when it comes to fairness matter.Some people would really take it seriously
and some wont really mind too much at all as long the current situation they are seeing is fair on their part.

I really depends though it just a matter on how serious you are into these things.

Provably fair has been a thing in only crypto gaming as far as I know. Has anyone checked if any fiat casino has any provably fair system implemented ever?

The good part about provably fair is that if you want to play a fair game and not get scammed by the casino or at least want to make sure you are not getting scammed by the casino then you have to play in crypto. That turns a lot of gamblers into crypto lovers as well, people who are not really interested in investment or trading part of crypto and just want to gamble and have fun that came into crypto world because of the provably fair casinos. That can't be too little number of people and too little amount of money that came into crypto world from fiat world just because of the provably fair fact.

As I always tell. Gambling websites and any gambling platform were made by the owner to earn the profit. Basically, it's a business you need to keep on running. In order for it to run, you have to make sure have profited from the users. Since that is the thing, you have to make sure to attract them with your death trap reserved for them.
The provably fair is a nice way to deceive people and make them feel the safeties and security of their bets. However, it doesn't convince
someone like me to get into there. Algorithms are not so mucch effective in running a business. And an algorithm must have a profit. Or else, they will make their gambling site as a large scheme of investment.

Very informative post.  But what are the provable fair verifiers for?
Can the verifier be used for checking other sites for avalability of provable fair ? I have always wondered if tools like that exists. Gambling sites can't just claim  provable fair, (even with their own verification tools) and expect us to believe....