What Mines actually is (so your tactics match the game)
Mines is a modern, casino version of the classic “Minesweeper.” On a 5×5 grid, you choose how many bombs are hidden, reveal safe tiles, and your cash-out multiplier increases with each safe pick; hit a bomb and the round ends. You can cash out at any time. Official guides for a leading “originals” version confirm the 5×5 grid, cash-out-anytime flow, and that it’s a chance game using provably fair randomness.
Several providers publish return-to-player (RTP) figures. Stake’s “Mines” lists 99% RTP (≈1% house edge), while the widely distributed Spribe “Mines” is cataloged around 97% RTP on industry listings. Different brands and versions vary—always check the game page you’re actually playing.
The core math: safe-pick probabilities without replacement
Each click samples the board without replacement: the chance your next pick is safe equals safe tiles remaining divided by unrevealed tiles remaining. More generally, the chance of surviving k safe picks with N total tiles and m bombs follows the hypergeometric distribution: P(survive k) = C(N−m, k) / C(N, k). This is the correct baseline for any “should I click again?” decision.
On a common 5×5 board (N=25) with 5 bombs (m=5), survival for the first few picks looks like this: first pick 20/25=0.80, then 19/24≈0.79, 18/23≈0.78. The cumulative chance to reach three safe picks is roughly C(20,3)/C(25,3) ≈ 49.6%; to reach five safe picks it drops to ≈29.2%. The key point is that risk increases as safe tiles are removed, because you’re sampling without replacement. (Numbers illustrative from the formula above.)
What RTP means for cash-out timing
In fixed-RTP implementations, the payout table is set so that, on average, any cash-out timing has the same expected value over the long run (e.g., ~99% on Stake’s version). Provably fair merely generates the random outcomes; it doesn’t change the house edge, which comes from the posted multipliers. That means “when to cash out” is about shaping variance, not beating the edge.
If you switch to a different supplier or venue, the RTP and multiplier curve can change. Spribe’s “Mines” is commonly listed at ~97% RTP, so the same risk behavior will lose faster, on average, than a 99% table—even though the pick probabilities are identical.
A probability-first framework for “hold or cash out”
Step 1: Know your next-pick survival
After k safe picks, survival on the next click is (N−m−k)/(N−k). With 25 tiles and 5 bombs, survival stays around 0.75–0.80 for the first few clicks, drifts toward 0.50 around the mid-teens, and drops sharply near the end as bombs dominate remaining tiles. Use this as your real-time risk gauge.
Step 2: Compare survival to the multiplier jump
In a “fair” world the cash-out multiplier after k safe picks would be 1 / P(survive k). A 99% RTP version reduces that by ~1%. For example, with 5 bombs, fair multipliers would be about 1.25× after one safe pick, ~2.02× after three, and ~3.43× after five; a 99% table trims each slightly. If the next-step multiplier jump looks exciting but the next-pick survival is already low, variance is exploding even though expected value stays flat.
Step 3: Set a personal survival threshold
Define a minimum next-pick survival you’re comfortable with and cash out the instant it falls below that number. Conservative players might set 0.70–0.75; aggressive players might run down to ~0.50 before cashing. Because survival declines as you progress, this creates an automatic “when to stop” rule that adapts to mine count. This rule optimizes for volatility control, not profit—important distinction with fixed RTP.
Choosing mine count: tailoring volatility on purpose
Fewer bombs mean high survival and low multipliers; more bombs mean low survival and steep multipliers. That’s why “1–3 bombs” sessions feel streaky-good with many small cash-outs, while “10+ bombs” sessions swing wildly. Official pages note you choose the mine count up front, and that multipliers rise with each safe tile—so pick a count that matches your risk tolerance before you ever click.
As a practical rule, start by lowering mine count if you plan to click many tiles before cash-out, and raise mine count only if you’re committing to early, pre-planned exits.
Worked examples (5×5 board)
• Five bombs, target three safe picks: P≈49.6%, fair multiplier ≈2.02×; a 99% table would offer slightly under that. If your next-pick survival threshold is 0.70, you can usually take 2–4 safe picks before crossing it.
• Ten bombs, target three safe picks: P≈19.8%—already harsh. The fair multiplier is ~5.05×, but next-pick survival falls fast; this is strictly for high-variance sessions and tiny stakes.
These numbers come straight from the hypergeometric formula and illustrate why “deep boards” with many bombs demand early cash-outs to keep risk manageable.
Pattern myths, streak chasing, and “systems”
Communities often claim special click patterns, “grids,” or bet-sizing systems can tilt the odds. In provably fair games, outcomes are produced from hashed seeds and nonces; the RTP is baked into the payout structure, not the click path. Even operator forums emphasise that provably fair randomness doesn’t grant an edge to any pattern. Use patterns only as personal routines to reduce hesitation, not as edge-creation.
Provably fair: how to sanity-check a round
Reputable operators and suppliers describe provably fair methods where the server seed (later revealed), your client seed, and a nonce generate the bomb layout or step outcomes. After the round, you can verify that your result matches the pre-committed hash. This proves integrity of randomness—not that the game is beatable.
Practical cash-out playbook
- Pick mines to match your variance budget; fewer bombs if you aim for multiple picks, more bombs only for short-run, small-stake shots.
- Define a next-pick survival threshold (e.g., 0.70) and pre-commit to cashing out as soon as survival dips below it.
- Treat RTP as a long-run tax. Stake’s version advertises ~99% RTP; Spribe’s is commonly ~97%. Higher RTP means slower expected loss, not profit.
- Ignore “systems.” Verify rounds via the provably fair page if provided; don’t chase patterns or streaks.
Responsible-gambling and compliance notes
Online gambling must be legal where you live. In Great Britain, operators must verify your identity (name, address, date of birth) before allowing you to gamble, and they cannot delay verification until withdrawal if they could have verified sooner. Use deposit limits and self-exclusion tools if needed.
FAQs
Does cash-out timing change the house edge?
No. In fixed-RTP implementations, cash-out timing changes volatility, not expected value. The edge comes from the payout table, not when you stop.
Is there an “optimal” number of bombs?
There’s no universal best. Fewer bombs favor frequent small multipliers; more bombs create rare but larger multipliers. Choose mine count to fit your survival threshold and stake size.
Are official RTPs the same everywhere?
No. Stake’s Mines advertises 99% RTP; Spribe’s Mines is commonly listed around 97%. Always check the specific game’s help or info panel.
How do I verify a round is fair?
Look for a “provably fair” page explaining server/client seeds and hashes; after play, compare the revealed server seed to the pre-round hash and regenerate the outcome.
Sources and further reading
• Stake blog — how Mines works on a 5×5 grid; cash-out any time; Mines RTP and provably fair note.
• Stake game page — Mines listed at 99% RTP (≈1% house edge); provably fair Originals.
• Spribe — Mines game overview; independent catalogs listing ~97% RTP.
• Hypergeometric distribution — the correct model for k safe picks without replacement.
• Provably fair explanations from iGaming providers.
• UK Gambling Commission — identity verification rules for remote gambling; player guidance.
