House Edge: What It Means and What It Does Not
Understand house edge as a long-run expected cost per unit wagered, with examples and common interpretation mistakes.
A 2% house edge means the game’s expected long-run loss is about $2 for every $100 of total wagering action. It does not mean you will lose exactly 2% of your bankroll in a session.
House edge is based on action, not starting bankroll
If you repeatedly recycle the same bankroll through many bets, total wagering can be much larger than the amount you deposited. Expected loss is calculated from total action.
Example
At $10 per bet for 100 bets, total action is $1,000. At a 2% house edge, theoretical expected loss is $20. Actual short-term results can be much higher or lower because variance dominates individual sessions.
Why speed matters
Two games with the same house edge can have very different expected hourly costs if one produces far more betting decisions per hour.
House edge versus RTP
For many games, a simplified relationship is RTP ≈ 100% − house edge. But published slot RTP is a theoretical return over very large samples, and game-specific terminology can differ.
What house edge cannot tell you
It does not indicate the probability of leaving one session ahead, how volatile the game is, or whether a particular wager is appropriate for your finances.
Expected dollars need total action
House edge is a percentage of wagered action. A 2% edge applied to $100 of total wagering has an expected cost of $2; the same edge applied to $10,000 of repeated action has an expected cost of $200. This is why game speed and repeated turnover matter.
Rule-specific, not brand-specific
The correct benchmark follows the rules/paytable, not the marketing name of the game. If a blackjack payout, roulette wheel or baccarat commission changes, the relevant expected return can change too.
Reproduce the arithmetic
The site’s Casino Mathematics Dataset and Worked Calculation Examples keep assumptions and formulas attached to the values so a reader can independently check the calculation.