Is Runelot Provably Fair? Full Explanation of How Our RNG Works

Short answer: yes, Runelot.com is provably fair. Long answer: that phrase gets thrown around so much by sketchy crypto casinos that it deserves an actual explanation, not just a badge in the footer. Here's how our system genuinely works — and how you can verify any bet you've ever placed in about 30 seconds.

The "trust me bro" problem

A normal online casino works like this: a random number gets generated somewhere on a server you can't see, and you're told what it was. You audit nothing. You verify nothing. If the house decides to tilt the odds a couple of percent in their favour on a slow Tuesday, you'd never know.

Provably fair flips that. The casino has to commit to a result before you bet, and prove it afterwards using cryptography that's been beaten on for decades. If the math checks out, the round was honest. If it doesn't, anyone in the world can see.

The three ingredients

Every bet on Runelot is the result of three things mixed together:

• Server seed — a long random string our backend generates. You see its SHA-256 hash up front, but never the raw value until you rotate.
• Client seed — a string *you* control. Set it to anything — your character name, your favourite skill, gibberish. As long as it's yours, the house can't game it.
• Nonce — a simple counter that ticks up by one with each bet. Round 1, 2, 3, and so on.

Run those three through SHA-256, do a tiny bit of math to convert the hash into a Crash multiplier / Mines layout / Dice roll, and that's your result. Deterministic — same inputs always give the same output.

How a round actually plays out

1. The sealed envelope

Before you bet, our server generates a fresh server seed and immediately publishes its SHA-256 hash. You can see this hash on the Provably Fair page and inside every game.

SHA-256 is a one-way street. We can show you the hash, but nobody on Earth can work backwards from the hash to the seed. The second we publish it, we're locked in — if we swap the seed later, the hash changes and you notice.

2. The round

You bet. The engine grabs the (still-sealed) server seed, your client seed, and the nonce for this round, hashes them, and converts the result into your outcome. Because *you* control the client seed, there's no way for the house to pre-pick a server seed that targets you specifically.

3. The reveal

Hit "Rotate Seed" in any game's Provably Fair panel. Three things happen:

1. The old server seed gets revealed in full.
2. A new sealed seed (and its hash) starts for the next batch.
3. You can now verify every single bet that used the old seed.

To verify, you re-run the same SHA-256 math with the now-public server seed, your client seed, and the nonce of any past bet — and you get the exact same result the game gave you. If it matches, the round was honest. If it doesn't, the entire industry hears about it.

Why this is bulletproof

A provably fair system makes three things impossible:

• Re-rolling: we can't generate a result, peek at it, dislike it, and re-roll — the seed is committed.
• Targeting individuals: we don't know your client seed when generating server seeds.
• Silent tilting: if we even shaved 0.1% off any payout curve, the math wouldn't match the published seeds.

The flip side is the house edge is completely transparent too. Crash sits at ~1% house edge, Dice ~1%, and the rest land in the standard low single-digit range for their game type. No hidden vig.

Doing the verification yourself

You don't have to be a cryptographer. Every game's history shows you the revealed server seed, your client seed, the nonce, and the result. Plug those into any public SHA-256 verifier (or any provably-fair checker — they're all over the internet) and confirm the round.

If you want to go deeper, our Provably Fair page has worked examples and the exact conversion formulas for each game.

What "fair" doesn't mean

Provably fair guarantees that the random number was honest. It doesn't guarantee you'll win — variance is variance, and the house has an edge on every game. What it does guarantee is that the edge is exactly what's published, no more, no less.

That's the whole point: you can lose, fairly and squarely, and *know* it was fair.

Bottom line

Runelot.com is provably fair top to bottom. You can verify every bet on every game. We never see your bet outcome before it's locked. And the only thing we know about your luck is whatever you tell us in chat.

Spin up Crash, set a custom client seed, and check the math for yourself.