You mostly cannot audit an RNG yourself. What UKGC RTS 7 requires, why no certificate has to be published, and what you can check instead.
Mostly you cannot, and the pages telling you otherwise are selling confidence rather than a method.
That is worth saying first, because the useful version of this question is not how to audit a random number generator. It is what the regulator already requires, who checked it, and which parts you can actually confirm.
In Britain, RTS 7 of the remote technical standards governs random outcomes. Its requirement is that "random number generation and game results must be 'acceptably random'".
The standard sets out how that is demonstrated: it must be possible to show "to a high degree of confidence that the output of the RNG" meets the criteria, "through, for example, statistical analysis using generally accepted tests and methods of analysis".
The implementation guidance names what is being tested for. The output should be uniformly distributed across the whole output range. It should be unpredictable. Random number generation should not reproduce the same output stream, meaning it should not cycle. And any seeding or re-seeding used should not introduce predictability.
A published certificate.
We looked for a requirement obliging operators or suppliers to publish RNG test certificates to players and did not find one in RTS 7. So an operator with no certificate on its website is not in breach of anything we can point to, and a site that does display one is going beyond what the standard asks.
This is the honest shape of the thing. The testing is required. Showing you the paperwork is not.
Three things, and they are worth more than a PDF you cannot verify.
Check who issued it and whether it names the specific game or system, then check whether the issuer is a testing house the regulator recognises.
A certificate with no issuer, no date and no scope is decoration. One that names a system version is at least a claim that can be checked against the version you are playing.
Not a statistics argument. A records request.
Ask the operator in writing for the game rules in force on the date you played, the game and version identifier, and your own play history for the session. Then raise it through the complaints procedure and, if unresolved, to the ADR entity named in the operator's terms. The complaint route is covered on its own page, with wording in a casino complaint email template.
A run of bad results is not evidence of a faulty RNG, and framing it that way is the quickest way to get a complaint dismissed. A game that did not behave as its published rules describe is a different and much stronger claim.
If a run of results has you thinking about stopping for a while, see cooling off, time out or self exclusion, which one you actually want.
UK Gambling Commission, Remote gambling and software technical standards, RTS 7, generation of random outcomes. https://www.gamblingcommission.gov.uk/standards/remote-gambling-and-software-technical-standards/rts-7-generation-of-random-outcomes
| Claim | Can you check it | How |
|---|---|---|
| The operator is licensed | Yes | The regulator's own register |
| The game matches its published rules | Yes | The rules screen, before and during play |
| You were told about a rules change | Yes | RTS 7D requires changes to be brought to your attention |
| The RNG is acceptably random | No, not yourself | Required under RTS 7 and demonstrated by statistical testing |
| A displayed certificate is genuine | Partly | Check issuer, date and the system version it names |
We found no such requirement in RTS 7. The standard requires the randomness and the demonstration of it. It does not oblige anyone to publish a certificate to players.
No, and a complaint built on that will fail. Long losing runs are ordinary at normal house edges. The claim with real force is that a game did not behave as its published rules say.
RTS 7's guidance sets the criteria: uniform distribution across the output range, unpredictability, no reproduction of the same output stream, and seeding that does not introduce predictability.
RNG requirements and quotes are from UKGC RTS 7 and its guidance. What to check and how to complain are general guidance. Last reviewed October 15, 2026.