Casino maths
RTP, Volatility and Hit Frequency: Three Different Measures
An average return cannot tell the whole story of a game. To understand why, separate the expected payout from the variation around it and the frequency of non-zero returns.
Two games with the same average
Imagine a one-unit stake in each of two fictional games. Game A returns one unit with probability 96%, and zero otherwise. Game B returns 96 units with probability 1%, and zero otherwise. These are teaching models, not descriptions of any listed slot.
The expected payout is 0.96 units in both cases: 1 × 0.96 for A and 96 × 0.01 for B. Both therefore have RTP of 96%. Yet their typical individual rounds look nothing alike.
Frequent returns need not be profitable
In A, most rounds return the stake, but no round makes a net profit. In B, almost all rounds lose the stake, while a rare payout produces a net gain of 95 units. Counting every non-zero payment as a win hides this distinction.
For example, receiving 0.40 units after staking one unit is a payout and a net loss of 0.60. When a report mentions hit frequency, establish whether it counts any payout, only stake recovery or strictly profitable outcomes. Those definitions can produce different percentages.
Variation measures a different property
The variance of a payout is its expected squared value minus the square of its expected value. For A, that is 0.96 − 0.96² = 0.0384. For B, it is 96² × 0.01 − 0.96² = 91.2384. The average is identical; the spread is dramatically different.
You do not need to calculate variance to read a game description critically. The example simply shows why a higher average return and a smoother sequence of outcomes are different claims. A label such as “high volatility” is also less precise than a disclosed numerical model.
What a short sample cannot establish
A few rounds might contain none of B's rare payouts or several of them. Either result can occur without changing the underlying probability. A short demonstration therefore cannot reliably identify an exact RTP or measure how often rare features occur.
Use the game's rules to understand what the figures actually describe. Do not interpret low volatility as protection from losses, or high volatility as a promise of a large payout within your session. Neither measure supplies a deadline for a win.
Related reading
For adults aged 18 and over. Educational content, not a promise of profit. Read our responsible gambling guidance.
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