How an RNG produces randomness
Most digital casino games run on a PRNG (Pseudo-Random Number Generator) — a deterministic algorithm that starts from a seed and produces a sequence of numbers with statistical properties indistinguishable from true randomness, even though it is technically calculable if someone knew both the seed and the algorithm. The seed is continuously refreshed from entropy sources (system clock, internal counters, hardware noise), which makes predicting the next output infeasible in practice. Every slot spin, dealt card, or crash-game multiplier is the result of a call to the RNG at that exact instant — there is no pattern, cycle, or "due to pay" window a player or operator can exploit.
A game's declared RTP is the mathematical outcome of how odds were configured inside the RNG. A game with a 96% RTP has its RNG configured so that, across the distribution of possible outcomes, 96% of wagered value returns as prizes over millions of rounds in aggregate. That is why RNG certification and audited RTP go hand in hand: certifying the RNG is, in practice, confirming that the RTP advertised to players is the RTP actually implemented in the code.
Certified RNG vs Provably Fair
Traditional casino games (slots, roulette, digital blackjack) rely on lab-certified RNGs because the algorithm runs on the provider's server and the player has no independent way to verify a single result. A subset of crash games and some crypto-native titles instead use Provably Fair, a mechanism where the outcome is derived from a cryptographic hash the player can verify after the round to confirm it was not manipulated.
| Feature | Certified RNG | Provably Fair |
|---|---|---|
| Where it runs | Provider's server | Algorithm with a verifiable hash |
| Verification | Independent lab, before launch | Player, after each round |
| Predominant model | Slots, table games, live casino | Part of the crash-game segment |
| Accepted under Brazilian regulation | Yes, the required model | Depends on additional provider certification |
What Brazilian regulation requires
Under Law No. 14,790/2023, overseen by the SPA/Ministry of Finance, game providers must have their systems — including the RNG — certified by an internationally recognized testing lab before the game can go live under a licensed operation in Brazil. The labs most used across the global market and accepted as reference points are eCOGRA, GLI (Gaming Laboratories International), and iTech Labs; each audits the generator's randomness, confirms the declared RTP matches the RTP actually implemented, and revalidates certification periodically. For an operator, this means provider due diligence has to include checking for a valid RNG certificate — not just the RTP figure quoted in sales material, which carries no probative value before the regulator without the certificate behind it.