Transparency
Verify a draw
Every PrizeProof winner is chosen by a commit-reveal protocol combining a pre-published commitment, a frozen entry pool, and public randomness from the drand beacon. No participant — including PrizeProof staff — can bias the outcome without it being publicly detectable.
The protocol
How a PrizeProof draw works
1. Commitment, before the competition opens
We generate a secret and publish a cryptographic commitment to it — a one-way hash — the moment a competition opens, before a single entry exists. The database itself refuses to open a competition without one, and refuses to create a commitment once any ticket has been sold. So the secret is always fixed before anyone can enter.
2. Entries, one shared pool
Paid and free postal entries are allocated from the same counter and receive sequential ticket numbers in one pool. Confirmed tickets can never be edited or deleted.
3. Close & snapshot, the pool is frozen
When entries close, the complete list of tickets is fixed and published as a snapshot — with a hash proving nothing in it can change afterwards. At the same moment, the exact drand randomness round to be used is fixed, as a deterministic function of the close time. Nobody can choose a favourable round.
4. Public randomness
The winning entropy comes from drand, an independent public randomness beacon that publishes a new verifiable value every few seconds. The value for the committed round does not exist until after the pool is already frozen — so it cannot be predicted or chosen in advance.
5. The draw, deterministic and auditable
The secret, the pool hash and the public randomness are combined with HMAC-SHA256 to produce a result, then an unbiased index into the entry pool is selected by rejection sampling. Every one of these inputs is published, so anyone can redo the arithmetic and get the same winner.
6. Reveal & verification
After the draw, the secret is revealed and everything above is published: the commitment, the full entry pool, the randomness used, and the result. Run the numbers yourself, or use the verification tool on each competition's page.
Results
Drawn competitions
Open any competition below to see its full commitment, entry snapshot, beacon value and result — and to run the verification yourself.