Provably Fair vs Certified RNG: What Each One Actually Proves 

Provably fair and certified RNG are routinely presented as competing answers to the same question. They are not. One lets you verify a single round you personally played. The other confirms that a whole system behaved correctly when a laboratory examined it.

A casino that only has one of them has a gap.  The distinction is worth getting right, because the marketing tends to blur it, and because the games you are most likely to play are usually covered by the mechanism people talk about least.  Key takeaways  ● Provably fair proves one round was not altered after you bet.

It says nothing about long-run payout percentages.  ● Lab certification proves the system matched its declared mathematical model at the time of testing.

It cannot be checked per round by a player.  ● Most provably fair systems use HMAC-SHA256 with a server seed, a client seed and an incrementing nonce.  ● Third-party slots from large studios are generally covered by lab certification rather than per-round verification.