You can personally verify the fairness of every round when you play Provably Fair games at a crypto casino. This technology lets you confirm that the casino didn’t tamper with the results, so you don’t need to simply trust the site to host fair games. It has become the gold standard for blockchain casino fairness, powering popular originals like Plinko, Crash, and Mines, plus certain slots and table games.
We’ll explain how Provably Fair gambling works. You’ll discover the three key components – server seeds, client seeds, and nonces – and how to verify a game result yourself. We’ll also help you find trustworthy Provably Fair casinos.
What Does Provably Fair Mean?
Provably Fair is a system that lets you independently confirm that a casino game’s results weren’t manipulated. Rather than trusting the operator or a third-party auditor, you can mathematically verify each outcome yourself.
Before you place a bet, the casino cryptographically commits to a random value that it can’t change afterward. Your own device contributes a second random value, which the casino can’t predict. The game combines both to generate each result, so neither you nor the casino can rig the outcome.
Traditional online casinos ask you to trust that their Random Number Generators are fair. A Provably Fair casino removes that leap of faith by handing you the tools to audit every round. If the operator tampered with a single result, the verification math simply wouldn’t add up.
How Provably Fair Works
Provably Fair technology uses cryptographic algorithms, which let you confirm that the casino didn’t tamper with the results. There are three components:
- Server seed: A random string of characters generated by the casino. You’ll get a hashed server seed before playing, and the hash is irreversible.
- Client seed: You contribute this string of characters. It ensures that the casino doesn’t have full control over the outcomes.
- Nonce: Short for “number used once.” This is a counter, which ensures that each result is unique, even if it uses the same server seed and client seed.
The game combines the server seed, the client seed, and the nonce to deliver the result of each round. You’ll then get an unhashed version of the server seed. You can plug it into a verifier tool, along with the client seed and the nonce, to confirm that the results weren’t manipulated.
Most Provably Fair games use SHA-256, a mathematical function that turns any piece of data into a unique 64-character string called a hash. It only works one way. You can’t reverse the hash to reveal the original data.
That’s why casinos show you a hash of the server seed before you bet. It commits them to that seed, without exposing it. Even changing a single character in the seed would produce a completely different hash, so any tampering after the fact is instantly detectable when you compare the revealed seed against the original hash.
Server Seed
The casino generates the server seed before you play. You’ll only see a hashed version of the seed, but it will be revealed after you rotate your seed pair. Just rotate the seeds to get an unhashed version of the server seed.
Client Seed
You supply the client seed. This is the piece that makes it impossible for the casino to rig the results. Your browser or device can create a client seed for you, but you can enter your own seed if you prefer. It’s best to change the default client seed.
Nonce
This is a counter, which increases after each round. It usually starts at 0 or 1, and then increases by 1 with each bet. For example, let’s say you’re playing Plinko. The nonce might be 0 on the first ball you drop, 1 on the second, 2 on the third, and so on. This ensures that each result is unique, even though the server seed and client seed remain the same.
How to Verify a Game Result Yourself
Verifying the result of a Provably Fair game is pretty straightforward. Just follow these steps:
- Save the server seed hash. Before betting, the casino displays a hashed (encrypted) version of its server seed, usually in the provably fair or fairness settings. Copy and save it.
- Place your bets as normal. Every bet you make is numbered with a nonce, which increases by one with each wager. You’ll need this later.
- Rotate your seed pair. Casinos only reveal the unhashed server seed once it’s no longer in use, so head to your fairness settings and request a new seed pair. The old server seed will then be revealed.
- Check the hash matches. Run the revealed server seed through a SHA-256 calculator and compare the output to the hash you saved in step one. If they match, you can confirm that the casino committed to that seed before you bet.
- Recalculate the result. Enter the server seed, your client seed, and the bet’s nonce into the site’s verifier or a third-party tool. The recalculated outcome should match the result you saw in-game.
If both checks line up, the result was verifiably fair. If they don’t, contact the customer support team to complain – and consider finding a better casino.
Provably Fair vs. Traditional RNG Casinos
Traditional online casinos rely on Random Number Generators (RNGs) to deliver the results of their slots and table games. Independent labs like eCOGRA, iTech Labs, and GLI audit these RNGs to confirm that the results are genuinely random and fair.
This system works, but it’s built entirely on trust. You’re relying on the auditor’s stamp of approval, and you have no way to check an individual spin or hand yourself.
Provably Fair casinos shift the power to the player. Every single round generates a cryptographic fingerprint that you can verify independently, without having to trust the casino, an auditor, or anyone else.
However, it’s important to note that traditional RNG-based games aren’t inherently unfair. If you play at a licensed casino that hosts games verified by reputable auditors, you can rely on the results to be fair, random, and in line with the stated return to player (RTP) rates.
The real difference is transparency. RNG certification proves the system is fair overall, while Provably Fair proves each specific result was fair. If you want verifiable certainty, that distinction matters.
Which Games Are Provably Fair?
Provably Fair technology is mainly used to power crypto original games. These are some of the most popular options:
- Plinko: Drop a ball onto a pegged board, and it will make plinking noises as it bounces off various pegs. The ball will eventually fall into one of the slots at the bottom of the grid. Each slot has a multiplier, which determines your payout.
- Crash: A vehicle will fly through the sky, and a multiplier will increase your payout with each passing second. Your goal is to cash out before the vehicle crashes. If it crashes, you’ll lose your bet.
- Mines: These games are inspired by minesweeper. You reveal tiles on a grid, hoping to find gems rather than hidden mines. Each safe pick increases your multiplier, and you can cash out anytime, but hitting a mine ends the round and forfeits your bet.
- Limbo: Pick a target multiplier and then watch the game generate a random result. If the generated number meets or exceeds your target, you win. Higher targets mean bigger payouts, but lower odds.
- Dice: (Set a target number and bet on whether the roll lands over or under it. Adjusting your target changes both your win probability and payout, giving you direct control over risk.
- Keno: This is a popular lotto-style game, which lets you pick up to 10 numbers on a grid. The game will then draw the winning numbers at random. Your payout will be determined by how many matching numbers you picked.
- Hilo: A card is dealt face-up, and you bet on whether the next card will be higher or lower. Correct guesses build a multiplier chain you can cash out at any point.
Many crypto casinos make their own versions of these games. Studios like BGaming and Spribe also make Provably Fair versions of these arcade-style games, which are available at many leading crypto casinos. Extra options include Wheel, Tower, Chicken, Diamonds, and Rock, Paper, Scissors.
It’s rare to find classic casino games that use Provably Fair technology. However, BGaming stands out by launching a wide range of Provably Fair games. They include table games like roulette, blackjack, and baccarat, plus video poker. Some BGaming slots are also Provably Fair, including Aztec Magic Deluxe, Lucky Lady’s Clover, and Avalon: Lost Kingdom.
Limitations of Provably Fair
Provably Fair technology verifies game results, but nothing else. A casino could run perfectly fair games and still delay withdrawals, impose predatory terms, or refuse to pay out. Fair outcomes don’t guarantee that the casino is legit.
The house edge also remains fully intact. Verification proves the results weren’t manipulated, but the casino still has a mathematical advantage on each game. That means you need above average luck to earn a profit.
It’s also important to actually verify the results. Many players never bother, which weakens the system’s accountability.
Finally, the technology is only available on a handful of games. Most slots and virtual table games aren’t covered by Provably Fair tech, and it can’t be used on live dealer games either.
How to Find Provably Fair Casinos
Here’s how to check if a crypto casino offers Provably Fair games:
- Look for a dedicated fairness or “Provably Fair” page explaining its verification system.
- Search for Provably Fair original games. Each game will have a “Fairness” or “Provably Fair” button. You can press it to check out the seeds and find the verification tool.
- Look for games from providers known for using the technology, such as BGaming and Spribe.
You can then vet the casino. Confirm the Provably Fair casino has a license from a renowned international regulator, and make sure the site has a long track record of treating players fairly and paying out on time.
Conclusion
Provably Fair technology gives you something traditional casinos never could: mathematical proof that each result was generated fairly. By understanding server seeds, client seeds, and nonces, you can audit any round yourself in minutes.
Just remember that fair games don’t automatically mean the casino treats players fairly. Payout history, licensing, and security still matter. To skip the legwork, check out our list of the best crypto casinos, where fairness is a key part of our vetting process.
Frequently Asked Questions
Provably Fair is a system that lets you personally confirm that the casino didn’t manipulate the results of a game. You can run the unhashed served seed, the client seed, and the nonce through a verification tool after each round. If the outcome is the same, you’ve proved that the casino didn’t tamper with the results.
You can rotate and reveal the unhashed seed, and then plug into a verification tool with your client seed and the nonce. Either use the site’s verifier or a third-party verifier online. Compare the recomputed result to the recorded one. If they match, the game round was verifiably fair.
Not necessarily – a casino might host Provably Fair games, but it could still refuse to pay out your winnings. Finding a casino that offers Provably Fair games is a great starting point, as you can personally audit the fairness of each round. However, it’s also important to focus on licensing, security measures, payout history, and player feedback when determining whether a casino is legit.
No, only a small percentage of crypto casino games use Provably Fair technology. They include games like Plinko, Dice, Crash, and Mines, plus certain slots and table games from providers like BGaming. Most other games use RNGs, but you can’t personally confirm the fairness of each round, so you need to trust the independent auditors.
Yes, all Provably Fair casino games have a house edge. That means the casino has a slight mathematical advantage over the players. Just stick to games with a low house edge. For example, Plinko and Mines from BGaming both have a slender 1% house edge.
A server seed is a random string of characters generated by the casino, while a client seed comes from your browser or device. In Provably Fair games, the two are combined with a nonce to determine each result. You can then confirm that the outcomes weren’t manipulated after you placed your bet.
Ilija is a CCN writer with 7 years of experience covering all things crypto. Ever since a fateful run-in with Litecoin in 2013, he's been an avid investor and writer in the space. When he's not maniacally hacking away at his keyboard, Ilija spends his time either hiking in nature or holed up in his apartment gaming.
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