Martingale: Ruin Risk at the CasinoMartingale: Ruin Risk at the Casino

Classic martingale doubles the bet after each loss on near even-money propositions (red/black). One win recovers losses + 1 unit net in theory, while table and bankroll allow it.

In practice, short losing runs are common. Stakes explode: 1, 2, 4, 8, 16, 32, 64… after ten losses you need 512 units for the eleventh hand.

18+: it is not a positive-EV strategy; house edge remains.

Casinos cap even-money bets. Progression hits max bet before you “get even”, locking a large loss.

Even without a cap, long adverse runs have non-zero probability. Ruin risk grows with session length.

On European roulette, ~2.7% edge (higher with double zero) makes the system asymmetric: frequent small wins, rare large losses psychologically toxic.

To survive N losses in a row you need about 2^N − 1 units reserved for the next bet, while respecting max. N=8 → 255 units tied up.

Players underestimate N because short runs dominate memory. Long tails dominate P&L.

No variant (grand martingale, anti-martingale) removes edge; they reshuffle variance.

Flat betting at ~1% bankroll unit, session stop-loss, lower-edge games (blackjack basic strategy) if you play tables.

Treat expected hourly cost as entertainment price, not investment.

If “get even” urge appears, stop immediately (18+).

Written ban on doubling after losses; fixed unit; timer; no credit; session log.

Reject “foolproof systems” sold online.

If gambling harm appears, use self-exclusion / local help.