The question "How long free spins last?" is usually about how a slot hands out its wins from one spin to the next. Two slots can list the same return and still feel like different games, because the return says nothing about how the money arrives. Volatility and hit frequency describe that part: how often a spin pays anything, how large the rare wins are and how long the dry spells last. Together they decide what a fixed budget is likely to buy in playing time.
Measured returns drift away from the theoretical figure over any stretch a person can play, and the gap narrows only across millions of spins. Tracking sites that pool results from many players show this clearly: a game can run far above or below its figure for weeks. Demo modes normally use the same maths as real play, so a free session shows the rhythm of a game, although a short demo run says as little about the true return as a short paid one.
Volatility measures how widely results scatter around the average return. A game rated low pays modest amounts at a steady pace, and a game rated high concentrates its return in rare, large wins, often inside a bonus feature. Studios describe it on scales of three or five levels, sometimes with lightning bolts or bars instead of numbers, and the scales are not comparable between studios. Choosing a level is a matter of taste and budget, while the cost over the long run stays put.
A session budget is easier to judge when it is counted in spins. Dividing the money set aside by the stake gives the number of spins it covers before any wins, and on a volatile game a long run without a meaningful payout is a normal event within that count. Lowering the stake stretches the same budget across more spins and gives the rare features more chances to appear. Raising it shortens the session without improving the odds of any one spin.
Common questions
How should a slot session budget be measured?
In spins: divide the money set aside by the stake to see how many spins it covers before any wins, and expect long dry runs on volatile games.
How is slot volatility shown to players?
Studios describe it on scales of three or five levels, sometimes as lightning bolts or bars, and those scales cannot be compared between different studios.
Why do measured slot returns differ from the stated figure?
Over any stretch a person can play, results drift from the theoretical figure; tracking sites show games running far above or below it for weeks at a time.
What is a maximum win cap on a slot?
Many slots limit the largest win a single spin can produce, often as a multiple of the stake; once reached, the round ends and further winnings are forfeited.