500 Casino Classics verifier
Paste a revealed 500 seed, game seed or Crash hash. This page recomputes the selected Classic with 500’s published CodePen math — HMAC-SHA256 or SHA-256, in your browser. It is not on the unified /verify page yet. After the page loads, nothing is sent to a server.
What this page implements
Three fairness families
Crash is a pre-generated hash chain salted with Bitcoin block #811500. Dice, Mines, Towers, HiLo, Plinko and Cases mix a revealed server seed, your client seed and a per-round game seed. Wheel and Roulette use a daily global secret plus the round number.
53-bit floats
Most 500 checkers take the first 13 hex characters of a SHA-256 or HMAC digest and divide by 2^52. That is the same 53-bit construction 500 documents as Math.pow(2, bits - 1). Dice is the exception: a 4-byte float times 10001 / 100.
Not on this page
Keno, Limbo and Diamonds — the 500 Originals that landed in 2025 — stay off until 500 publishes a fairness snippet for them. Legacy pre-December 2023 Wheel and Roulette modulo mappings are also omitted.
Not the unified calculator
Stake, Shuffle and BC.Game stay on /verify. This URL is 500-only so you can check the numbers against 500.casino/provably-fair before any tab is added there.
Does any of my data leave this page?
No. After the page loads, hashing runs through the browser Web Crypto API. Seeds are not posted anywhere — including not to 500 Casino.
Where do I copy the seeds?
Open the Classic, then Fairness. Client seed and game seed are on the bet. Rotate the client seed to reveal the old server seed. Crash uses the public round hash, not your personal pair. Wheel and Roulette use the unhashed daily secret plus the round number from the fairness table.
Why is there a game seed as well as a nonce?
500’s seed-pair Classics issue a unique game seed per round. That is not Stake’s incrementing nonce. Paste the game seed from the bet exactly. Duels replace it with a future EOS block id after every seat is filled.