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Fairness basics

What sits behind the “RNG tested” seal

Online slots and many table games use a random number generator. Licensing and lab testing do not make every spin a win — they set rules for how outcomes are produced and checked.

RNG in one paragraph

A random number generator produces the numbers that map to reel stops, card draws or roulette results in software games. On a UK-licensed site those games must meet technical standards the Commission expects operators and suppliers to follow. Live dealer games use real equipment filmed in a studio; the fairness story there is about procedures and camera coverage rather than a software RNG for the physical ball or cards.

Independent testing labs

Studios and operators commonly engage accredited test houses — names you may see include eCOGRA, GLI, iTech Labs and BMM. Labs examine game mathematics, RNG behaviour and whether published return-to-player figures match the build under test. A seal means a product version passed defined tests; it is not a personal guarantee that your next session will return a specific amount.

Abstract illustration of certified random number blocks
Seals refer to tested builds and processes, not individual player outcomes.

What to look for as a player

On UKGC-licensed operators such as those we compare on the homepage, game info panels often show supplier name, rules and RTP where published. Prefer brands that keep that information reachable. If a page waves a lab logo but hides company and licence details, treat the polish as secondary to the UKGC footer mark and account protection tools.

Myths worth dropping

RNGs do not “owe” a payout after a dry run. Hot and cold streaks are how random sequences feel to humans, not a signal the next spin is due. Changing bet size mid-session does not reset a secret cycle. If play stops feeling like entertainment, use limits or GamStop.

Reel Craft Office is independent and affiliate-funded. This page is educational — we do not certify games ourselves.

Licence document motif
UK licensing and lab testing work together; neither replaces personal limits.