155API
Provably Fair

Verify a Round

From a settled round to an independent green check — three ways, no trust required


Verification always follows the same shape: take a settled round's published values, feed them to the open-source verifier, and it recomputes the outcome from the seed in your browser. A green result means the seed reproduces exactly what was paid, and that the seed links back to a root committed before the round began.

Only settled rounds reveal a seed

The secret server seed is published only after a round settles — never while betting is open. Before then, the only public value is the commitment (the seed's fingerprint). This is what stops anyone, including us, from knowing an outcome early.

The easiest path: in-game

Open a past round

In any game, open a previous round from the history — the past-rounds panel or a bet in your history. A provably-fair panel opens.

Read the verdict

The panel shows the commitment (published before the round), the revealed server seed, the chain root, and a live re-computation of the result. A green check means the seed reproduces the paid outcome and links to the published root.

Check it independently

Tap Verify independently to open the standalone verifier with every value pre-filled. It runs the same algorithm client-side — nothing is sent to any server.

Look up any round: support.marbles.xyz

The support lookup finds any round by ID and shows the same Provable Fairness card, plus a one-click Verify independently hand-off. Useful for support threads, disputes, or spot-checks.

The standalone verifier

The open-source verifier recomputes a round entirely in your browser. You can use it two ways:

Or verify by hand. Pick the game type, paste the round's published values, and press verify:

  1. Choose the game — CCTV crash, CCTV counting, or Classic games.
  2. Paste the revealed server seed and the commitment (published before the round).
  3. Paste the chain root and chain index (the seed's position in the committed chain).
  4. Paste the game-specific result values (the multiplier and house edge for crash; the outcome, boundaries and weights for counting; the entrants and finishing order for classic).
  5. Press verify — the tool recomputes and compares.

What the values mean

Every value is public and appears in the round's reveal:

ValueWhat it is
CommitmentSHA-256 of the server seed, published before betting closed. Proves the seed existed and was fixed in advance.
Server seedThe secret that decides the outcome, revealed after the round settles.
Chain rootThe published starting point of the pre-committed hash chain.
Chain indexWhich link in the chain this round used. The verifier hashes the seed index times and confirms it reaches the root.
Result valuesGame-specific — the crash multiplier, the counting outcome + boundaries + weights, or the classic winner / finishing order.

Green means two things

A green verdict certifies both that the seed reproduces the paid result and that the commitment came from the round-open event. If a round is missing its pre-round commitment, the verifier deliberately withholds the green check — it will not claim more than it can prove.

When it doesn't match

A red result on a genuine reveal should never happen. If you ever see one:

  • Re-check you copied the whole seed and commitment (no truncation).
  • Make sure the round has settled — an in-progress round has no seed yet.
  • Confirm the game type matches the round.

If a correctly-copied, settled round still fails, that's exactly what provable fairness is for — contact us with the round ID and the verifier link.

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