Stop guessing.
Start verifying.
Paste the three numbers from your case opening. We recompute the outcome cryptographically, on your device, with zero network requests, and prove whether the result was set fairly.
Four steps.
None touch our servers.
Grab your seeds
Paste them here
We recompute
Compare
Check any roll
in 20 seconds.
Step 1Where did you play?
Using Ripster box / upgrade: HMAC-SHA256 over clientSeed:noncedetails
HMAC-SHA256 keyed with the server seed over clientSeed:nonce. The first 8 hex characters become a 32-bit integer, divided by 2^32 and multiplied by 100 for a roll in [0, 100). Items are sorted by item ID and selected by cumulative probability: the first item whose cumulative probability is at least the roll wins.
Where to find your numbers on Ripster.gg:
- Before rolling, copy the Server Seed Hash from the Provably Fair modal (also recorded per roll in Account History).
- After the roll, open the Provably Fair modal to copy the Server Seed, Client Seed and Nonce.
- Change your Client Seed anytime in Account Settings; doing so reveals the current Server Seed so all past rolls become verifiable.
Source: Ripster.gg's own fairness page
Step 2Paste your numbers
Runs entirely on your device via your browser's built-in cryptography. Don't take our word for it: open DevTools → Network, click the button, and watch: zero requests.
One round, proven live.
Three seeds lock in, HMAC-SHA256 resolves the outcome, the reel lands, and the round stamps FAIR because the math says so, not because anyone promises.
What this proves
What it cannot prove
Re-run every roll from a seed pair at once and export the table. Good for auditing a full session.
Paste your pull history and see your real hit rate against the published odds. A smell test, not proof.
Want the full picture of how each formula is sourced and checked? Read the methodology.
Built to be checked, not believed.
Every verification runs locally in your browser. Don't take our word for it: open DevTools, watch the Network tab, and click Verify. Zero requests. Every formula cites the platform's own fairness page. Read the methodology.
In plain
English.
No HMAC jargon required. If you got here from a Discord argument, start at the top.
What does “provably fair” actually mean?+
It means a site commits to its random result before you play, using cryptography, so it cannot secretly change the outcome after seeing your play. This tool lets you re-run that math yourself, on your own device, to check any past roll.
Do I need an account? Do you see my seeds?+
No account, and no. Every calculation runs inside your browser using its built-in cryptography (the Web Crypto API). Nothing you paste here is sent anywhere. You can confirm it: open your browser's DevTools, go to the Network tab, and click Verify. You'll see zero requests.
My result doesn't match. Was I cheated?+
Usually not. Most mismatches are input mistakes. Check that you pasted the revealed server seed (not the hashed one), the exact client seed, and the right nonce for that specific roll, and that you picked the right platform and game. If it still fails after that, save your numbers and a screenshot: that evidence is exactly what a dispute needs.
Can this tool predict my next roll?+
No, and nothing can: the next roll depends on a server seed that is still secret. Anyone selling a “predictor” is scamming you. Verification only checks completed rolls after the seed is revealed.
If a roll verifies, is the site safe to use?+
Not necessarily. A passing check proves this specific outcome wasn't manipulated. It says nothing about whether a withdrawal will actually go through, or whether the wider site is trustworthy. Fair math and a trustworthy business are different things.