Mines on Rainbet, bigger boards and all.
Rainbet plays the same core game as Stake and BC.Game, but it's one of the very few platforms that lets you scale the board past the standard 5×5. That single feature changes every number underneath it, so it's worth understanding before comparing Rainbet's payouts against the Mines simulator.
5×5 is the floor, not the only option.
Rainbet lets you pick a board size — 5×5, 6×6, 7×7, or 8×8 — before you even set a mine count, a feature only a handful of platforms currently offer. More tiles on the board means every probability underneath the game changes: an 8×8 grid has 64 tiles instead of 25, so the same mine count behaves completely differently.
The multiplier formula itself doesn't change — it's still (fair odds) × (RTP factor) — but every term inside it depends on the total tile count. Swap 25 tiles for 64 and every C(n,k) combinatorial term in the calculation is different, which means every multiplier is different too. This site's calculator and payout chart model the standard 5×5 board only; if you're playing Rainbet on a 6×6 or larger grid, treat those numbers as directional, not exact.
A shuffle, not just a hash, decides the layout.
Seed pair drives the shuffle
Rainbet feeds your server seed, client seed, and nonce through HMAC-SHA256, and uses the resulting bytes to run a Fisher-Yates shuffle across every tile index on the board.
The first slots become mines
Whatever tile indices land first in that shuffled order become the mines — a clean, well-understood way to turn a hash into an unbiased random layout across boards of any size, 5×5 through 8×8.
Same verification model as everywhere else
Because the mechanism is seed-pair based like Stake and BC.Game, you can rotate your seed to reveal the previous server seed and independently re-run the shuffle to confirm your round wasn't altered.
Sources disagree on Rainbet's exact RTP: some cite the crypto-standard 1% house edge (99% RTP) shared with Stake and BC.Game, others put Rainbet specifically at 96.5% RTP — a meaningfully bigger edge. We couldn't confirm which figure is accurate for which grid size from Rainbet's own materials, so we're not going to paper over the conflict with a made-up number. This calculator and the payout chart both use the 1% convention; if you're betting real money on Rainbet, check the in-game info panel for the number that actually applies to your bet.
Questions specific to Rainbet's version.
Why does Rainbet's Mines math look different from this calculator?
Two possible reasons: you're playing a board bigger than 5×5 (which changes every underlying probability), or Rainbet's actual RTP differs from the 99% convention this calculator uses — sources disagree on that figure, so treat any mismatch as expected rather than a bug in either the game or the calculator.
Can I play Mines on an 8×8 grid on Rainbet?
Yes — Rainbet offers 5×5, 6×6, 7×7, and 8×8 board sizes, which is unusual; most crypto casinos only offer the standard 5×5. A bigger board means more tiles, more mines to choose from, and a different multiplier curve than the one this site models.
How are Rainbet's Mines multipliers calculated on the standard 5×5 board?
The shape of the formula is identical across every board size — only the tile count plugged into it changes.
The formula (any grid, N total tiles)
- Win chance for m mines and k safe reveals is C(N−m, k) ÷ C(N, k) — on the standard board, N = 25.
- Fair multiplier is 1 ÷ win chance — what the payout would be with zero house edge.
- Actual multiplier is the fair multiplier × the RTP constant, whatever that is for the specific board and RTP Rainbet is running.
Worked example — 5×5 board, 3 mines, 3 tiles revealed
- Ways to pick 3 safe of 22: C(22,3) = 1,540
- Ways to pick 3 of all 25: C(25,3) = 2,300
- Win chance: 1,540 ÷ 2,300 = 66.96%
- Fair multiplier: 1 ÷ 0.6696 = 1.49×
- At the 99% convention: 1.49× × 0.99 = 1.48×
Is Rainbet's Mines provably fair?
Yes — it uses the same server-seed/client-seed/nonce model as Stake and BC.Game, run through HMAC-SHA256 and a Fisher-Yates shuffle to place mines. You can rotate your seed pair to verify past rounds independently.
What's the biggest win possible on Rainbet Mines?
Commonly cited at up to $1,000,000, with a maximum multiplier reported around 10,000× on the standard configuration — figures from third-party sources rather than Rainbet's own published documentation, so treat them as approximate.
Does a bigger grid change the house edge, or just the tile count?
The tile count is what visibly changes — 64 tiles on an 8×8 board instead of 25 gives you finer, more gradual multiplier steps rather than the sharper jumps a 5×5 board produces. We haven't found confirmation that Rainbet targets a different edge per board size versus just reusing the same target across all four — treat that as unconfirmed rather than assumed.
Is there a best mine count or grid size on Rainbet?
No — mine count and grid size both change variance, not any edge you can exploit. A bigger board with the same mine-to-tile ratio plays out similarly in the long run, just in smaller, more frequent steps. The full trade-off for mine count is broken down on our Mines strategy breakdown.