STOCHASTIC ABSORPTION // BANKROLL LONGEVITY

Slot Bankroll Decay & Spin Survival Calculator

Calculate the mathematical median spins until bankruptcy and expected session duration under negative expectation. Quantify how configurable RTP cuts (96.5% vs 94%) and high spin velocity accelerate bankroll burn rates.

CAPITAL & TURNOVER PARAMETERS

Total Session Bankroll ($) $200

$20 $200 $1,000 $2,000

Wager per Spin ($) $1.00

Slot Theoretical RTP (%) 96.50%

88.0% (Severe) 94.0% 96.5% (Max) 99.0%

Play Velocity (Spins / Hour) 600 spins/hr

200 (Slow) 600 (Normal) 1,200 (Turbo)

MEDIAN SPINS UNTIL RUIN

5,714 spins

At house edge: 3.50%

EXPECTED SURVIVAL DURATION

9 hrs 31 mins

At current speed

EXPECTED TOTAL TURNOVER

$5,714.29

28.6x deposit turnover

MATHEMATICAL DRAIN PER HOUR

-$21.00 / hr

Mathematical friction

SURVIVAL PROBABILITY DECAY CURVE S(n) Survival Probability (1.0 → 0.0)

Frequently Asked Questions

How does the turnover formula calculate median spins until ruin?

Under negative expectation, every spin recycles a fraction of the bet back into the bankroll. The theoretical total wagered volume before absorption equals Bankroll / (1 - RTP). Dividing total turnover by bet size gives expected lifetime spins: E[Spins] = Bankroll / [Bet * (1 - RTP)].

What is the impact of dropping from 96.5% RTP to 92.0% on session survival?

At 96.5% RTP, the house edge is 3.5%. At 92.0% RTP, the house edge is 8.0% (a 128% increase). This cuts expected session spins and playtime by more than half for the exact same deposit.

Why does turbo spin mode drain bankrolls so quickly?

House edge is a rate per wagered dollar, not per minute. Accelerating from 400 spins/hour to 1,000 spins/hour in turbo mode increases hourly turnover by 150%, thereby multiplying the hourly dollar loss by 2.5x.