Online Gambling & Industry
RNG meaning
RNG stands for random number generator, the software or hardware that produces statistically random numbers to determine outcomes in online gambling games.
Key points
- An RNG uses a seed value and algorithm to generate a sequence of numbers, which the game maps to outcomes like slot symbols 4.
- Each result is intended to be independent of previous results, ensuring fairness 2.
- Regulators require RNG output to be uniformly distributed, unpredictable, and non-repeating 3.
- In wider gaming, RNG refers to any random outcome generation, not limited to gambling 4.
How an RNG works in online gambling
- The RNG starts with a seed value, often derived from a timestamp or user action 4.
- An algorithm processes the seed to produce a sequence of numbers that appear random 4.
- The game maps each number to a specific outcome — for example, which symbols land on a slot reel 4.
- The process repeats continuously, with each result independent of the last 2.
Regulation and testing
In the UK, the Gambling Commission sets technical standards for RNGs used in remote gambling. The output must be acceptably random: demonstrably random to a high degree of confidence, with uniform distribution, unpredictability, and no repeating output streams 3.
Independent testing labs like eCOGRA and Gaming Laboratories International (GLI) certify RNGs to ensure they meet these standards 4. The certification process verifies that the RNG produces a uniform distribution of numbers and that the sequence cannot be predicted or reproduced 5. Testing also checks that the RNG does not synchronise with other system components or produce patterns that could be exploited 3.
Common questions
What is RNG in gaming?
In gaming, RNG stands for random number generator, the system that produces unpredictable outcomes — such as loot drops, critical hits, or map generation. It is the same core concept as in gambling but applied to gameplay mechanics rather than wagering.
Where this term is used
Not the same as
- RNG slots — the same core concept but specifically applied to slot games, where the RNG determines which symbols appear on the reels
Related terms
Sources
- Remote gambling and software technical standards (RTS) - 2 gamblingcommission.gov.uk Defines RNG and lists the games it applies to in remote gambling.
- Regulatory returns guidance - 2 - Random number ... gamblingcommission.gov.uk Specifies the required properties of RNG output: uniform distribution and unpredictability.
- Guidance to licensing authorities - RTS 7 – Generation of ... gamblingcommission.gov.uk Details the 'acceptably random' standard and the requirement for no repeating output streams.
- Ensuring Fair Play with RNG Testing and ... ecogra.org Explains how an RNG uses a seed and algorithm to generate outcomes.
- iGaming & Esports Random Number Generator Certification gaminglabs.com Describes the certification process for RNGs, including verification of uniform distribution and unpredictability.
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.