You might be able to use a card counting strategy in a real casino, but the tables are turned when you switch to online versions of the game. The odds shift with the use of Random Number Generators, but how random are they?

Not much unlike a continuous shuffling deck after each hand, Random Number Generators (RNGs) are a computer algorithm that theoretically makes each dealt hand “truly” random, with no bias towards player or dealer.

However, there are those who speculate whether or not these RNGs are truly random, or whether the house to shift the edge towards them has doctored them.

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Here at, we’re going to give you the lo-down on everything you need to know about RNGs and playing blackjack online.

What are RNGs and how do they work?

A RNG is a computation device that is used to produce a sequence of numbers that have no pattern, and therefore appear completely random.

These are often used in computer programming for the generation of random events. Often these are used in scientific simulations, but they also serve an important role in online gambling software.

You can use a RNG to simulate throwing dice, flipping a coin, and also acts as a shuffle for playing cards. You’ll also find RNGs in use for modern slot machines.

The generation of random numbers in a computer program depends on what is called an algorithm, a mathematical formula used to create generate random values.

However, many computer programs fall short on being truly random and these are referred to as “pseudo-random number generators”.

These automatically generate long runs of numbers that show good random properties, but the sequence eventually repeats.

RNGs and online casinos

In an online casino, RNGs are used to give the element of statistical probability and randomness a kick.

However in computer programming, how this functions an RNG is used via an algorithm, but the computer must be given a starting number, this can be anything, like 2 or 25 and this is then put through a sequence of equation.

When you use that number, say 2, you’ll get the same result back each time, but playing online blackjack, this of course will need to be different.

To get a different result from the computer for each game, you’ll need to start with a different number than what was used previously, which is how pseudo-RNGs work.

The RNG, as an example, tells the computer to check the internal clock of the computer and uses the number of the second hand. So you would be able to have 60 different outcomes, which can be used in some applications but not ideal for an online casino.

A more sophisticated method is to use the number Pi, an irrational number with a never-ending sequence of digits, which has no repeating pattern if you wrote out the first billion digits.

So for the first billion digits, you could effectively generate effective random numbers, but if the player knew the sequence, it would be possible to break the code.

As a result, casinos use a combination of the two methods to generate random numbers, where the first “seed” uses the computer clock, which picks a point in the sequence to use.

So the seed generates a random number from the sequence then might pick to that number in Pi and uses numbers from then on.

Although it’s more common for the seed to just be plugged back into the formula and continues to generate random numbers that way, since it takes up less computer memory that way.

The effectiveness of this method will depend on the sequence used. However, risks with random number generators are certain genius players who might be able to predict the sequence or the sequences favor the player or the house.

Truly random?

Whether a casino offering blackjack games depends uses a truly random outcome in its RNG depends on a variety of factors. This depends on the algorithm used by the house or the seed used to generate the number.

However, there is a continuous debate on whether pure unpredictability can exist in programming or not. “True random numbers” are defined as those that cannot be predicted by any person using a formula, and these do exist.

While encryption programs can work this way, it’s not feasible to apply to online or mobile casino games, so the answer is no, casino games are never going to be truly random.

Although, the answer to the question of whether RNG in online blackjack are truly random scientifically comes out as “no”, you’d still have to be a genius with a powerful to crack the code.

So for simplicity’s sake, RNGs at good online casinos, for all purposes, are random.