Casino games are games of chance with a built-in house edge. No strategy, system or choice of timing changes the odds in the player’s favor over time, and most players lose money over the long run. Nobody should gamble money they cannot afford to lose. Comparing games by cost is a way to understand price, not a way to find one that wins.
Why edge alone is not enough
A percentage house edge tells you the expected loss per unit wagered. It does not tell you how many units you wager. Two games with the same edge can cost very different amounts per hour if one deals twice as fast or is played at twice the stake. Similarly, a game with a higher edge can cost less per hour if it is slow and played with small bets.
So to compare games on equal terms, convert each to the same unit: expected loss per hour. This is the idea behind the expected cost of play, extended with a time dimension.
The formula
Expected loss per hour = (rounds per hour) × (average amount wagered per round) × (house edge)
The first two factors multiplied together give total action per hour, sometimes called turnover. The third turns action into expected loss. Notice that this is a long-run average. In any single hour the real result could be a loss far larger than the estimate, or a win. Variation around the average is explained by standard deviation and by game variance.
Worked examples
Every number below is hypothetical and chosen to be easy to check. They are not claims about any particular venue or game.
Single-zero roulette. Assume 30 spins per hour and a bet of 10 units per spin on one even-money bet. Action is 30 × 10 = 300 units. The edge is 1/37, about 2.70 percent. Expected loss: 300 × 0.0270 ≈ 8.11 units per hour.
Double-zero roulette, same pace and bet. Action is again 300 units. The edge is 2/38, about 5.26 percent. Expected loss: 300 × 0.0526 ≈ 15.79 units per hour. The only change was the extra zero, and the hourly cost nearly doubled. This is the same effect described for the extra zero at the wheel.
A blackjack table, assumed 0.5 percent edge. Assume 60 hands per hour at 10 units. Action is 600 units. Expected loss: 600 × 0.005 = 3 units per hour. The edge depends heavily on the rules at the table and on whether decisions follow basic strategy, so treat 0.5 percent as a placeholder.
A slot machine, assumed 5 percent edge. Assume 600 spins per hour at 1 unit. Action is 600 units. Expected loss: 600 × 0.05 = 30 units per hour. Slot edges differ widely between machines, and a machine’s return to player is a long-run figure, so 5 percent here is only an illustration.
| Game (hypothetical) | Action per hour | Assumed edge | Expected loss per hour |
|---|---|---|---|
| Single-zero roulette | 300 | 2.70% | about 8.11 |
| Double-zero roulette | 300 | 5.26% | about 15.79 |
| Blackjack | 600 | 0.5% | 3.00 |
| Slot machine | 600 | 5% | 30.00 |
The ranking by edge alone would have put slots and double-zero roulette close together. The ranking by hourly cost separates them clearly, because of speed and the amount of money moving through the game.
Things that complicate the estimate
Multiple bets per round. If you place several bets per spin or hand, the amount wagered per round is the total of all of them, not the largest one. Side bets add action at their own, often higher, edge.
Average bet, not the starting bet. If you change bet sizes, use the average amount wagered. For betting systems that raise stakes after losses, the average bet will be larger than the base unit, and the expected loss rises accordingly. Such a system never changes the edge per unit wagered.
Pushes and ties. Some rounds return your stake. Whether you count them in “rounds per hour” depends on which edge figure you use, because edges are usually quoted per initial wager. Matching the basis of the edge to the basis of the count avoids double counting.
Rounds per hour vary. A crowded table deals fewer hands per player than a quiet one. Online play and automated games can run much faster than live ones. The effect of speed of play on expected loss is a large enough topic to have its own article.
Edges are estimates. Rule changes, number of decks, pay tables and payout notation all shift the edge. If you are unsure of the edge, your hourly figure is only as good as that assumption.
What the number means and does not mean
An estimate of 8 units per hour does not say you will lose 8 units in an hour. Your actual result is the sum of many random outcomes, with a spread far bigger than the average. Over a short session, the spread dominates. Over many hours, results tend to gather around the average, as the law of large numbers describes. The same reasoning is why theoretical loss and actual results in one session can differ widely.
Used sensibly, the figure helps with one thing: putting a price on entertainment. If a night of play has an expected cost, you can ask whether that is a cost you are comfortable with, and set a spare-money budget and time limits accordingly. If an expected cost or a session feels uncomfortable, or gambling is causing difficulty, support services can offer confidential help.