CSDB · CS2 Gambling
Provably Fair Verifier
Check a CS2 gambling site’s result yourself, in your own browser. Nothing is sent to us or to the operator — a verifier that asks the operator whether the operator cheated would not be worth much.
1. Did the site reveal the seed it committed to?
This is the check that matters, and it works on any operator that publishes a hashed server seed before a round. Rotate your seed on the site, copy the revealed server seed and the hash it showed you beforehand, and paste both here.
2. Recompute a roll from the seeds
Once the commitment checks out, this derives the outcome the seeds produce. It implements the HMAC construction that CSGORoll, Rain.gg and Hunt.gg all document — operators vary, so if your site publishes a different hash width or slice, change it here rather than assuming this is wrong.
What this proves, and what it does not
A passing commitment check proves one specific thing: the result of that round was fixed before you bet and was not altered afterwards. That is a real guarantee and worth having.
It is also much narrower than the phrase suggests. It says nothing about whether the advertised drop rates are honest, whether the house edge is what the site claims, whether the operator is licensed or solvent, or whether it will process your withdrawal. A site can be scrupulously provably fair and still take a very large margin from you, provably, on every single round. Most “this site is rigged” complaints describe a normal losing run rather than a broken seed — and this tool is how you tell the two apart.
Operators whose scheme we have read
These are the sites in our database that publish a documented provably-fair scheme, with what each one actually commits to. Where a site claims fairness without publishing a verifiable scheme, it is not listed here.
| Site | What it documents | |
|---|---|---|
| CSGOEmpire | Publishes a hashed server seed before each round and reveals it afterwards, with a user-editable client seed. Roulette, coinflip and case battles each document their own scheme. | Review |
| CSGORoll | publicSeed, serverSeed and nonce, with the verification JavaScript published and runnable in the browser. Its RNG changed in October 2022, so older rolls need a different script. | Review |
| Clash.gg | SHA-256 commit/reveal with an editable client seed — but explicitly scoped to PvE games only. The case-battle algorithm is not documented. | Review |
| CSGOBig | A hashed server seed combined with third-party randomness from Random.org, whose sequential serial numbers let you audit for gaps — a stronger design than seed-only schemes. | Review |
| Datdrop | Commit-reveal with a secret hash and salt, so you can prove the server seed was not swapped. PvP modes use Random.org tickets drawn only after all players have joined. | Review |
| Rain.gg | The best-documented of the set. Publishes working code per game — HMAC-SHA512 over the server seed keyed with clientSeed:nonce:step — and uses an EOS block hash for battles. | Review |
| Hunt.gg | Documents two schemes rather than one. Single-player games use a hashed server seed committed up front, a client seed the player can set to anything, and an incrementing nonce; rotating the server seed reveals the old one so past rounds can be checked. Multiplayer games replace the client seed with an EOS blockchain block hash committed to before the game starts, which is the right design for a game where one player could otherwise influence the result. It also ships a hash verifier so a revealed seed can be checked against its published hash. | Review |
Frequently Asked Questions
- What does provably fair actually prove?
- One thing: that the result of a specific round was fixed before you bet, and was not altered afterwards. The site commits to a server seed by publishing its hash, you contribute a client seed, and after the round the server seed is revealed so you can recompute the outcome. If the revealed seed hashes to the published value, the result could not have been swapped after the fact.
- What does it not prove?
- Almost everything else people assume. It does not prove the advertised drop rates or house edge are honest — the operator chooses those and the seed scheme says nothing about them. It does not prove the site is licensed, solvent, or that it will process your withdrawal. And it does not prove the site is not simply taking a large margin on every round, fairly and provably. Treat it as one box ticked, not a safety rating.
- Does this tool send my seeds anywhere?
- No. The hashing runs in your browser using the Web Crypto API, and nothing is transmitted to CSDB or to the operator. That is deliberate: a verifier that asks the operator whether the operator cheated is not a verifier.
- My roll does not match what the site showed. Has it cheated?
- Probably not. Operators differ on hash width, on how many hex characters they consume, and on whether the nonce starts at 0 or 1 — so a mismatch is far more often a formula difference than dishonesty. Check the operator’s own documentation first. A failed commitment check, where the revealed seed does not hash to the published value, is the serious one.
- Which sites can I check with this?
- The commitment check works on any operator that publishes a hashed server seed before the round, which is most sites claiming provable fairness. The roll derivation implements the HMAC construction documented by CSGORoll, Rain.gg and Hunt.gg, and used with variations by many others.