Provably fair casinos publish the math behind their random results and give you tools to verify every bet after the fact. The gold standard includes a documented seed-commit scheme, a per-bet verifier, and ideally open tooling that third parties can reproduce. Stake, Primedice, Roobet, Bustabit, BitStarz Originals, Bitcasino.io, TrustDice, and FortuneJack all state they offer provably fair mechanisms on at least part of their game catalogs; coverage and transparency vary by brand and by game. Studio-made slots inside these casinos often rely on traditional RNG certifications instead of per-bet proofs, so you should check per-game details.
How “provably fair” works in practice
Most crypto casinos use a commitment scheme where the casino commits to a hashed server seed before you bet and you set or accept a client seed; combined with a nonce, those inputs generate each result. After you finish a session or rotate seeds, the casino reveals the server seed so you can recompute outcomes and confirm nothing changed mid-play. Stake’s implementation documents HMAC-SHA256 over server/client seeds and a nonce, and it ships a public verifier.
An alternative on-chain model uses verifiable randomness such as Chainlink VRF, where each random value ships with a cryptographic proof that smart contracts verify on chain before using it. This is common in web3 games and lotteries, and you’ll see it marketed as “provably fair randomness.”
Important scope note: many third-party studio slots inside crypto casinos are audited via traditional RNG certifications (GLI, iTech Labs, eCOGRA) rather than per-bet proofs; both are fairness approaches, but they are not the same.
Our rating rubric for “who truly delivers”
- Public, technical fairness docs that describe seeds, hashes, and algorithms.
- A built-in per-bet verifier or calculator you can run yourself.
- Independent reproducibility: open-source verifier or widely reproduced code.
- Breadth: how much of the catalog is provably fair vs. only RNG-certified.
- Bonus points for on-chain proofs (e.g., VRF) where applicable.
Showdown results
Stake
What you get: full fairness docs and a self-serve verifier covering Stake Originals (Crash, Dice, Plinko, Mines, etc.). Docs spell out HMAC-SHA256 over server/client seeds and nonce; Stake lists per-game conversion rules and a calculator to re-compute results. Third-party provider titles typically rely on studio RNG certification.
Verdict: excellent transparency and tooling on Originals; check each game’s info panel for fairness method on non-Originals.
Primedice
What you get: one of the longest-running dice sites (est. 2013) with thorough provably-fair docs and help articles. Independent write-ups detail the server/client seed model used to verify each roll.
Verdict: a benchmark for provable dice; narrowly focused catalog, but top-tier clarity.
Roobet
What you get: a fairness page stating every bet is verifiable on Roobet, with Originals like Crash marketed as provably fair. As with most multi-provider casinos, not all third-party studio games expose per-bet proofs.
Verdict: solid for Originals; verify per-game fairness notes on provider titles.
Bustabit
What you get: a crash pioneer with community-visible “seeding events” and multiple third-party verifiers and libraries on GitHub. Openness makes independent auditing easier than most.
Verdict: transparency leader for a single game type; excellent reproducibility.
BitStarz (Originals and BGaming titles)
What you get: a “Provably Fair Games” hub and step-by-step guide to using the BitStarz Originals verifier; BitStarz also notes many BGaming titles are provably fair and verifiable. Not all 6,000+ games are provably fair—check each title.
Verdict: clear tools for the Originals set; mixed catalog overall, so verify game-by-game.
Bitcasino.io
What you get: help-center copy stating the site uses provably fair tech and provides tools to verify randomness; licensing details under Curaçao’s CGA are publicly posted. Catalog spans many providers, so verification method varies by game.
Verdict: states provable fairness and shows license info; confirm proofs per title.
TrustDice
What you get: a provably fair dice focus with pages explaining how to verify results; public materials also mention RNG audits on broader content.
Verdict: good for dice and in-house games; third-party content relies on audits.
FortuneJack
What you get: blog and FAQ positioning provably fair alongside RNG certificates; forum discussions show the community actively tests claims—use the verifier links the casino provides and escalate any discrepancies.
Verdict: says the right things; double-check proofs and read T&Cs on a per-game basis.
Side-by-side snapshot you can use
| Brand | Per-bet verifier | Clear seed docs | Open tools/code | On-chain VRF use | Catalog note |
|---|---|---|---|---|---|
| Stake | Yes (calculator) | Yes | Algorithm documented | Not advertised | Originals provably fair; providers RNG-certified. |
| Primedice | Yes | Yes | Community verifiers | Not applicable | Dice specialist; deep docs. |
| Roobet | Yes | Yes (fairness page) | Limited | Not advertised | Originals provably fair; check provider games. |
| Bustabit | Yes | Yes | Multiple GitHub libs | Not applicable | Crash only; strong reproducibility. |
| BitStarz (Originals/BGaming) | Yes (Originals) | Yes | Guide provided | Not advertised | Only part of catalog provably fair. |
| Bitcasino.io | States tools | States | Not public | Some titles may use RNG audits | Mixed catalog; verify per title. |
| TrustDice | Yes (dice) | Yes | N/A | Not advertised | PF for dice; RNG audits elsewhere. |
| FortuneJack | Verifier links claimed | Yes | N/A | Not advertised | Uses PF and RNG certs; check game pages. |
When a game is not “provably fair,” what should you expect?
If a slot or live-dealer title doesn’t expose seeds or a per-bet proof, it should rely on a certified RNG and periodic audits against a standard like GLI-19. Studios and casinos typically publish who tested the RNG and when; always look for a current certificate or a licensor/auditor listing.
If a game claims “provably fair via blockchain,” look for VRF or a similar on-chain scheme where the proof is validated before use in a contract. Marketing claims should align with verifiable docs.
How to verify a bet in under two minutes
- Open the casino’s fairness page and copy your client seed, server seed hash, and nonce from the bet history. Stake and Primedice document these inputs clearly.
- Paste them into the site’s calculator or an open-source verifier for the specific game (e.g., Bustabit verifiers on GitHub).
- After rotating seeds, compare the revealed server seed to the original hash. A mismatch is a red flag.
Caveats and common misconceptions
Provably fair does not change the house edge; it only proves nobody tampered with randomness. For most third-party games at big casinos, fairness depends on RNG certification rather than per-bet proofs, and that distinction matters when you are picking what to play.
Community threads and forums can surface useful tests and complaints, but treat them as starting points, not proofs. Always rely on official verifiers and, when relevant, on-chain proofs.
