Check a round.

Every round with money on it is drawn on Solana. This page reads the round straight from Solana, in your browser, not from our server, and checks it step by step.

Or tap one of the latest rounds below.

The six checksThis round, checked on Solana

  1. The round belongs to Roulana’s table.
  2. The fingerprint of the secret seed was sealed on Solana before the first bet.
  3. Betting closed.
  4. The seed revealed afterwards matches the fingerprint.
  5. The block mixed in was made after betting closed.
  6. The formula gives the number the program published and paid.

Latest rounds with money on it

What the checks rely on

Steps 5 and 6 read the program’s own receipt in the reveal transaction: Solana keeps a block’s hash for only a few minutes, so the program writes it down when it draws the number. The checks show that the program did what its published rules say. The program can still be upgraded with the owner’s key: see Upgrades.

Check it without this page

  1. On Solana’s explorer. Every step of a check links to the Solana transaction it reads.
  2. On your own computer. Download verify-round.py and run python3 verify-round.py <round address>. Nothing to install: it talks only to Solana, and it is short enough to read first.
  3. By hand. The formula and a short example are on the Solana page.