Roulette Session Loss Calculator

Calculate your expected loss and result probability ranges for a roulette session. Understand the impact of variance on short-term results.

Formula:Expected Loss = Bets × Spins × House Edge

Expected Loss

$8.10

4.1% of bankroll

P(Any Profit)

41.7%

Session Std Dev

$38.68

P(Lose All)

100.00%

$

Amount you're bringing to the table

$

Typical bet per spin

25-40 typical for live tables

Session length

Determines house edge

Affects variance (not house edge)

Session Summary

Total Spins
60
Total Action
$300
House Edge
2.7%
Betting Units
40

Probable Result Ranges

68% Confidence (1σ)
$-47 to $31
95% Confidence (2σ)
$-85 to $69

Best 5% case: Up $68 | Worst 5% case: Down $84

Risk Assessment

P(Any Profit)
41.7%
P(Lose 50%+)
99.1%
P(Lose All)
100.00%

Roulette Session Simulator

Monte Carlo simulation with 1,000 iterations

$

Your initial capital

%

Your expected advantage

%

Percentage of bankroll per bet

Total bets to simulate

Key Facts

  • •Expected loss = Total wagered × House edge
  • •European: 2.70%, American: 5.26%, French La Partage: 1.35%
  • •Variance is higher for long-shot bets (straight-up, etc.)
  • •68% of sessions fall within 1 standard deviation of expected
  • •Longer sessions = more certain losses (law of large numbers)

Frequently Asked Questions

How much should I expect to lose at roulette?

Your expected loss equals total bets × house edge. For example, betting $10 per spin for 100 spins on European roulette ($1,000 total action), your expected loss is $27 (2.7%). Actual results will vary widely due to variance.

What is the house edge on European vs American roulette?

European roulette has a 2.70% house edge (single zero). American roulette has 5.26% (double zero). French roulette with La Partage has just 1.35% on even-money bets. Always prefer European or French when available.

What is the probability of losing my entire bankroll?

This depends on your bankroll size relative to bet size and session length. With 40 betting units and even-money bets, the risk of losing everything in a typical session is low (usually under 5%). This calculator shows your specific risk.

Why do straight-up bets have higher variance?

Straight-up bets pay 35:1 but win only 1 in 37 spins. This creates huge swings - you can lose many bets in a row then win big. Even-money bets are more stable with nearly 50% win rate and 1:1 payout.