Provably fair blackjack solves a problem every online player has thought about: how do I know the next card was not chosen after I bet? In a provably fair game the casino locks in its part of the randomness before the hand and shows you a fingerprint of it. You add your own part. After the hand, the casino reveals its part, and anyone can recompute the cards.
On this page
The three ingredients
| Ingredient | Who sets it | When you see it |
|---|---|---|
| Server seed | the casino | its hash before you play; the seed itself after you rotate it |
| Client seed | you, or your browser by default | always; you can change it |
| Nonce | counts hands with the current seed pair | always |
The game feeds the three into a cryptographic function and turns the output into card positions. Because the server seed is fixed and hashed before you play, the casino cannot change it after seeing your bet. Because you set the client seed, the casino cannot pick a server seed that produces a known deck.
How to check a hand
- Before playing, note the hashed server seed in the game's fairness settings, and set your own client seed if you like.
- Play as many hands as you want; the nonce counts them.
- Rotate the seed pair. The casino reveals the old server seed and starts a new one.
- Hash the revealed seed with the stated algorithm and compare it with the hash you noted. They must match.
- Recompute a hand. Enter the server seed, client seed and nonce into the casino's verifier or an independent one. The cards must match the hand you played.
If any step fails, the game is not provably fair, whatever it claims.
What provably fair does not prove
- The rules. A provably fair blackjack game can still pay 6:5 or hit soft 17. Read its rules as at any table.
- The payout of a side feature. A multiplier or bonus round has its own pay table and edge.
- That the casino will pay. Withdrawals depend on the casino's terms: caps and ID checks.
Play live and RNG blackjack with crypto.
Crypto casinos with provably fair originals
- 1
Vave
4.9/5Studio tables only; no provably fair originals listed.
Latcas B.V. · since 2022 · Licence Curaçao OGL/2024/1676/0905 · 90 coins: BTC, ETH, USDT, LTC · Sportsbook on the same account
- 2
Metaspins
4.8/5Runs its own provably fair originals next to studio tables.
Metaspins N.V. · Licence Curaçao OGL/2024/1063/0437 · 8 coins: BTC, ETH, USDT, BCH · Provably fair originals · Sportsbook on the same account
- 3
Shuffle
4.8/5Runs its own provably fair originals next to studio tables.
Natural Nine B.V. · since 2023 · Licence Curaçao OGL/2024/1337/0628 · 20 coins: BTC, ETH, LTC, SOL · Provably fair originals · Sportsbook on the same account
- 4
DuckDice
4.8/5Runs its own provably fair originals next to studio tables.
Zentari Limitada · Licence Anjouan ALSI-202509013-FI1 · 10 coins: BTC, ETH, LTC, SOL · Provably fair originals · Sportsbook on the same account
- 5
BitStarz
4.5/5Runs its own provably fair originals next to studio tables.
Gareton B.V. · Licence Curaçao OGL/2024/165/0185 · Provably fair originals
- 6
Stake
4.3/5Runs its own provably fair originals next to studio tables.
Medium Rare N.V. · Licence Curaçao OGL/2024/1451/0918 · Provably fair originals · Sportsbook on the same account
- 7
BC.Game
4.2/5Runs its own provably fair originals next to studio tables.
Operating company not stated · since 2017 · Licence Anjouan ALSI-202410011-FI1 · 150 coins: BTC, ETH, XRP, LTC · Provably fair originals · Sportsbook on the same account
Casinos with provably fair originals first, then by score.
These casinos run their own provably fair games next to studio tables. The list of originals changes; check each casino's originals section for a blackjack game and read its rules screen.
Provably fair, live and RNG compared
| Provably fair original | Live studio table | RNG studio table | |
|---|---|---|---|
| Who deals | casino's seed system | a dealer from a shoe | studio's generator |
| You can verify a hand | yes, yourself | you watch the deal | through audits only |
| Speed | fast | slow | fast |
| Rules | set by the casino | set by the studio | set by the studio |
Common questions about seeds
Should I change my client seed? You can, and it does no harm. It guarantees that a server seed cannot have been prepared for your default seed.
Why can I only check a hand after rotating? Revealing the server seed while it is still in use would let you compute the next cards. Rotation retires it first.
Is the hash enough on its own? No. The hash proves the seed did not change; recomputing the hand proves the cards came from that seed.
Every operator we rate for blackjack sits in one table on the crypto blackjack casino list.
Questions and answers
What is provably fair blackjack?
A blackjack game, usually a casino's own original, where the cards are generated from seeds: a server seed the casino commits to in advance, a client seed you control and a counter for each hand. After the hand you can recompute the cards and confirm they were not changed.
How do I verify a provably fair blackjack hand?
Rotate or reveal the server seed in the fairness menu, then enter the revealed server seed, your client seed and the nonce into the casino's verifier or an independent one. The cards it produces should match the hand you played.
Does provably fair mean a lower house edge?
No. It proves the deal was not altered after you bet. The edge still comes from the game's rules and payouts, which you should read as at any table.
Which crypto casinos have provably fair originals?
Among the casinos we compare, Stake, BC.Game, BitStarz, Metaspins, Shuffle, DuckDice and Wolf.bet run provably fair originals. Check each casino's originals list for a blackjack game.