Verify a round

Before selling the first card, the platform publishes the SHA-256 of the seed. At the end, it reveals the seed. Paste both below and check — the arithmetic runs in your browser, and nothing is sent anywhere.

Redoing the draw yourself

The ball sequence comes out of the seed through SHA-256 in counter mode, with no randomness library involved:

bloco_i   = SHA-256(semente + ":draw:" + i)
uint32_j  = 4 bytes consecutivos, big-endian
n         = 90 (ou 75)

# inteiro uniforme em [0, n), sem viés:
limite = floor(2^32 / n) * n
repetir v = próximo uint32 enquanto v >= limite
resultado = v mod n

# a urna é uma permutação de 1..n por Fisher-Yates
# usando essa fonte, consumida em ordem

The full procedure, card issuance included, is in the generator’s technical dossier.