WagerFormula
Probability
Gambler’s Fallacy: Why Past Spins Don’t Change the Odds
The gambler’s fallacy is the belief that past results change the next outcome. See the math with roulette, coin and dice examples,…
Probability in Gambling: Formulas and Worked Examples
How probability works in gambling: the four core formulas, worked roulette, dice and card examples, and a table of common bet probabilities.
Expected Value
Expected Loss Per Hour: How to Estimate Gambling Cost
Expected loss per hour = bets per hour × average bet × house edge. See the formula with worked roulette examples, comparison…
Expected Value Formula for Gambling: Worked Examples
The expected value formula for gambling, with worked roulette and betting examples, a table of EV by bet, and how EV becomes…
WagerFormula in Numbers
- Active Monthly Users Around the World
- 1M+
- Guides and Reviews
- 150+
- Topics
- 7
- Authors
- 2
House Edge
Craps House Edge: How Each Bet’s Edge Is Calculated
How the craps house edge is calculated for the Pass Line, Don’t Pass, Field, Any 7 and Place bets, with every step…
Roulette House Edge: Formula and Calculation
How the roulette house edge is calculated from true odds and payout odds, with worked examples and a table of European, American…
Variance
Law of Large Numbers in Gambling: What It Really Means
What the law of large numbers says about gambling: averages settle on the house edge while totals swing wider, with roulette and…
Variance in Gambling: Standard Deviation and Swings
How variance and standard deviation measure gambling swings, with roulette examples, the square-root-of-n rule and a table of session ranges.
Odds & Payouts
Gambling Mathematics
Kelly Criterion Formula: How It Works and Its Limits
The Kelly criterion formula explained with hypothetical worked examples, and why it gives a zero stake on every standard casino bet.
The Martingale System: Why the Math Doesn’t Work
The Martingale system doubles stakes after losses. See the formulas, losing-streak odds and why its expected value stays negative.
