Gambling terms, explained straight

Online Gambling & Industry

RNG full form

RNG stands for Random Number Generator: the hardware or software that produces random numbers to determine outcomes in slot games and other online casino games.

Applies to
Slot games, reel-based casino games, and other RNG-driven online gambling games.42
How it works
Uses a seed value and algorithm to generate numbers mapped to game outcomes, such as slot reel symbols.4
Regulation
The UK Gambling Commission defines RNG as hardware or software intended to produce statistically random outcomes.2

Key points

  • RNG outcomes are designed to be unpredictable, independent, and unbiased.25
  • In gaming machines, RNG is typically pseudo-random — algorithmically generated rather than physically random.1
  • RNG is not the same as Return to Player (RTP), which is the game's payout percentage.13

Where this term is used

Online RNG meaning Explains what RNG stands for and its role in gambling. Online RNG slots How RNG determines outcomes in slot machines. Online RNG certification The process of testing and certifying RNGs for fairness. Online Wagering meaning in betting Wagering means staking money or value on an uncertain outcome Online Casino wagering requirement A casino wagering requirement is a promotional condition Online Ecogra certification A seal that independent tests have confirmed an online gambling product

Sources

  1. How can gaming machines meet their %RTP if they are ... gamblingcommission.gov.uk Defines RNG as pseudo-random and distinguishes it from RTP.
  2. Remote gambling and software technical standards (RTS) - 2 gamblingcommission.gov.uk Provides the official UK definition of RNG and its technical standards.
  3. Remote game and/or software payment faults gamblingcommission.gov.uk Supports the distinction between RNG and RTP.
  4. Ensuring Fair Play with RNG Testing and ... ecogra.org Explains how RNG uses a seed and algorithm to generate outcomes.
  5. [PDF] GLI-11 Gaming Devices in Casinos gaminglabs.com Describes the intended properties of RNG outcomes.

Sources are drawn from regulators, universities and published research, and each one is labelled with what it actually is — a preprint is not called a paper. Bookmaker and affiliate pages are never cited here, because a page that sells betting is not a neutral authority on it.

Written and maintained by Ellis Warrender, writer and maintainer.

Last updated 28 July 2026. Spotted an error? Tell me and it gets fixed and logged on the corrections page.