
Slot machines have various acronyms to define various aspects of its design, and one player wonders how two elements interact with each other:
How do RNGs and RTPs affect one another?
Stacy F.
First, let’s review each of these acronyms and what they mean:
- The Random Number Generator (RNG) is how a slot’s outcome is determined – the number(s) (one or more is used depending on the design of a slot) that is active at the millisecond that you press the spin button determines what the spin’s outcome will be.
- Return to Player (RTP), also known as payback percentage, is what a game is expected to return to a player in terms of payouts as a percentage of the overall wagers, over the long term. Slots tend to be designed with around a half dozen choices for casinos to select within a range of 85-98 percent, and casinos will select the one they wish to use for their floor.
So how do they affect one another? The RNG is working within a range of outcomes. The totality of all outcomes is what determines the RTP.
To offer a very simple example, if you had a million outcomes, and each one cost $1 to get, and you won $900,000 on those wagers, you’d have an RTP of 90 percent. That’s how the RTP is determined for a given game.
Because each outcome has an equal chance of coming up on the RNG, over time, after millions of spins, it’s expected that each outcome will come out roughly the same number of times.
So, the RNG being random within that range is how the RTP is achieved over time. And that’s how they affect one another. While they’re different parts of a slot machine’s design, they both have a key role in achieving what’s supposed to happen over time with a game, ensuring the casino makes money and the player gets paid back on their spins what they should as well.
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