# Provability Explained

#### SoftSwiss Card, Roulette and Slot games are Provably Fair, which means you can verify fairness of any game immediately after each round you play! Using cryptographics we make it easy for you to confirm that we (the Casino) cannot possibly cheat you. So how does Probability work?

### Game Mechanics

Before each game our server uses a certified, best-in-class Random Number Generator to generate a game outcome that is called *Result*. Quite naturally, it is unknown you before the game.

You are also able influence the result – like, for example, you would cut the deck of cards before dealing in a real-life card game. To do this, you provide us with a number representing your influence. This number is called *Client Seed*.

After you place your bets, the game happens and we calculate the *Final Result* of the game based on both the *Result* and *Client Seed*.

### What Verification Means

Verification is making sure that the *Result* used to calculate the *Final Result* was generated before you placed your bets and started the game. If you can prove that, it means the Casino didn’t tinker with the *Result* after you placed your bets and the *Final Result* is indeed random and fair.

### How to Verify Fairness

If the *Result* is unknown before the game, how can anyone make sure the *Result* remained the same before and after the game happened?

This is where cryptography comes into play. The *Result* is actually provided to the player before the game – but in an encrypted form.

Besides the *Result*, our server generates a random sequence of characters known as *Secret* and then puts the combination of the two through an algorithm called SHA-256 hashing function. The resulting hash is called *Hash{Result+Secret}*. It is visible to the

The hash looks like a long string of random symbols. Its most important property is that it’s virtually impossible to “reverse engineer” the hash and find out the input data (*Result+Secret*) used to calculate it. At the same time, if you do know the input, it’s really easy to calculate the actual hash.

So once the *Result+Secret* is shown to you after the game, you can take it and recalculate the hash yourself. You can use the widget on our site or any third-party hash calculator like QuickHash.com – it doesn’t matter as long as you use the same (SHA-256) algorithm to recalculate the hash.

If the hash you calculated matches exactly the hash we provided before the game, congratulations! Fairness has been proven!

#### There are slight differences in Probably Fair gameplay for different types of games. We explain them in more detail below.

### Provably Fair Roulette

- 1. From our game software perspective, the roulette wheel is modeled as a list of the tiles with numbers, from 0 to 36. We use our certified Random Number Generator to generate a random location at which the roulette wheel will stop in the next game. This spin is called *Result*.
- 2. We also generate a random string of characters called *Secret*. The Result and the randomly generated Secret are shown to you before the game, hashed with SHA-256. This hash is referred to as *Hash{Result+Secret}*.
- 3. We even let you have some effect on the game! You can “push” the wheel a little bit more. Choose a number from 0 to 36 (0 to 37 for American roulette) to push the wheel further by that amount of tiles when you hit “Spin”. You can either choose your own number or use one picked randomly for you. This number is called *Client Seed*.
- 4. Place your bets and play the game!!!
- 5. After the game is over, we show you the spin of the wheel generated by our server (*Result+Secret*), the hash we showed you before the game (*Hash{Result+Secret}*), the effect you had on this game (*Client Seed*), and the *Final Result*.

You can use the “Verify” button to prove that the spin (*Result+Secret*) matches the hash we showed you before the game. Or you can use any third-party hash calculator to prove it yourself!

#### How to verify manually

If you prefer not to use the verification widget on our website, you can check the game for fairness on another website. It’s very really easy to do!

- 1. Find a third party hash calculator that you trust. There are many of them, like online-encoder.com, quickhash.com or convertstring.com.
- 2. Select SHA-256 as your hashing algorithm.
- 3. Copy the Result+Secret field form the game, paste it into the input box of the third party calculator, and press “Generate” or “Encrypt”.
- 4. The resulting hash should exactly match the hash we showed you before the game! This proves we didn’t tinker with the initial spin after you placed your bets or had your influence on the game. All fair!

### Provably Fair Cards

- 1) At first, we generate a deck of cards. We use top-standard shuffling techniques to produce a unique and completely random deck of cards before each game. This deck, i.e. the sequence of cards, is called *Result*.
- 2) We also generate a random string of characters called *Secret*. The Result and the randomly generated Secret are shown to you before the game, hashed with SHA-256. This hash is referred to as *Hash{Result+Secret}*.
- 3) We even let you have some effect on the game! You can “cut” the deck of cards. Pick any number to determine the location where we should cut the deck. This number is called *Client Seed*. For example, if you enter 45 as your Client Seed, we will cut 45 cards from the top of the deck before dealing the cards and beginning the game.
- 4) Place your bets and play the game!!!
- 5) After the game is over, we show you the spin of the wheel generated by our server (*Result+Secret*), the hash we showed you before the game (*Hash{Result+Secret}*), the effect you had on this game (*Client Seed*), and the *Final Result*.

You can use the “Verify” button to prove that the spin (*Result+Secret*) matches the hash we showed you before the game. Or you can use any third-party hash calculator to prove it yourself!

#### How to verify manually

If you prefer not to use the verification widget on our website, you can check the game for fairness on another website. It’s very really easy to do!

- 1. Find a third party hash calculator that you trust. There are many of them, like online-encoder.com, quickhash.com or convertstring.com.
- 2. Select SHA-256 as your hashing algorithm.
- 3. Copy the Result+Secret field form the game, paste it into the input box of the third party calculator, and press “Generate” or “Encrypt”.
- 4. The resulting hash should exactly match the hash we showed you before the game! This proves we didn’t tinker with the initial deck shuffle after you placed your bets or had your influence on the game. All fair!

### Provably Fair Slots

- 1) From our game software perspective, each slot reel is modeled as a list of tiles in the order they appear. We use our certified Random Number Generator to generate a random location for each of the reels to stop at. This spin is called *Result*.
- 2) We also generate a random string of characters called *Secret*. The Result and the randomly generated Secret are shown to you before the game, hashed with SHA-256. This hash is referred to as *Hash{Result+Secret}*.
- 3) We even let you have some effect on the game! You can “push” each reel a little more. Choose a number to push the reels further along by respective amounts. You can either choose your own numbers or use ones picked randomly for you. The sequence of selected numbers is called *Client Seed*.
- 4) Place your bets and play the game!!!
- 5) After the game is over, we show you the spin of the wheel generated by our server (*Result+Secret*), the hash we showed you before the game (*Hash{Result+Secret}*), the effect you had on this game (*Client Seed*), and the *Final Result*.

#### How to verify manually

If you prefer not to use the verification widget on our website, you can check the game for fairness on another website. It’s very really easy to do!

- 1. Find a third party hash calculator that you trust. There are many of them, like online-encoder.com, quickhash.com or convertstring.com.
- 2. Select SHA-256 as your hashing algorithm.
- 3. Copy the Result+Secret field form the game, paste it into the input box of the third party calculator, and press “Generate” or “Encrypt”.
- 4. The resulting hash should exactly match the hash we showed you before the game! This proves we didn’t tinker with the initial spin after you placed your bets or had your influence on the game. All fair!