Gamba Originals verifier
Paste a revealed Gamba server seed, client seed and nonce. This page recomputes the selected Original with Gamba’s fairness worker — PBKDF2-HMAC-SHA512 of each seed, then HMAC-SHA256(derivedServer, derivedClient:nonce:round). Crash and Slide use the public hash chain instead. It is not on the unified /verify page yet. After the page loads, nothing is sent to a server.
What this page implements
BIP39-style seed stretch
Instant Originals do not HMAC the seeds you type. Gamba first runs PBKDF2-HMAC-SHA512(seed, \"mnemonic\", 2048), takes the first 32 hex characters of that digest, and hex-encodes those ASCII characters. Both the client seed and the revealed server seed go through that step.
HMAC-SHA256 byte stream
The derived server seed keys HMAC-SHA256 of derivedClient:nonce:round. Bytes are a continuous stream: round = floor(offset / 32). Four bytes become a float as b0/256 + b1/256² + b2/256³ + b3/256⁴.
Crash and Slide are public
Those two games do not use your personal seed pair. They HMAC the revealed round seed with the public hash seed and round id, then apply a 1% crash curve. Rotate nothing — paste the event’s public values.
Not the unified calculator
This URL is Gamba-only so you can check the numbers before any tab is added there. It is not on the unified /verify page yet. Stake, Shuffle, BC.Game and the other live tabs stay on /verify.
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.
Why is there a PBKDF2 step? Other casinos skip that.
Gamba’s fairness worker stretches every personal seed with the BIP39 salt “mnemonic” before HMAC. Pasting the already-derived hex as if it were the raw seed will not match. Use the client seed and revealed server seed shown in Fairness.
Each Original has its own seed. Is that right?
Yes. Gamba rotates Dice, Mines, Plinko and the rest independently. A nonce from one game is meaningless on another, even with the same typed client seed.
Why are some multipliers missing?
Wheel, Pump, Darts, Slice, Cash Hunt and Dragon Tower payouts live in Gamba coefficient tables that are not in the fairness worker. This page reports the draw the worker actually computes — pocket, path, burst index, floats — rather than inventing a payout.
Crash and Slide ask for no client seed. Is that right?
Yes. Those rounds are a public seed chain plus an external hash. Instant games still use your personal pair.