Three numbers on a slot's info screen tell you most of what you need to know. RTP is how much it pays back on average, volatility is how unevenly it pays, and max win is the most a single spin can pay. None of them tells you what will happen in your next session. This guide explains each one, with worked examples.
RTP: a long-run average
RTP, or return to player, is the share of all the money staked on a slot that it pays back over a very large number of spins. A slot with a 96% RTP pays back $96 for every $100 staked, on average, and keeps $4. That $4 is the house edge: 4% of everything you stake, not 4% of what you deposit.
Worked example: 1,000 spins at $1 is $1,000 staked. At 96%, the expected return is $960, an average loss of $40. Because wins are usually staked again, a $100 deposit can easily turn into $1,000 of stakes, so the average cost of that session is $40, not $4.
Over one session the real result can land almost anywhere. The same 1,000 spins might end $300 down or $500 up, depending on whether a bonus lands and what it pays. RTP describes millions of spins across all players, not yours.
Volatility and hit frequency
Volatility describes how the RTP is paid out. A low-volatility slot pays small wins often; a high-volatility slot pays little most of the time and saves much of its RTP for rare, big bonuses. Two slots with the same 96% RTP can feel completely different.
| Low volatility | High volatility | |
|---|---|---|
| Wins | Frequent and small | Rarer, sometimes large |
| Bonus rounds | More often, modest pays | Less often, a wide range of pays |
| A $100 budget at $1 a spin | Usually lasts a while | Can be gone quickly |
| Max win | Often a few thousand times the bet | Often 10,000x or more |
Hit frequency is how often a spin pays anything. A hit frequency of 25% means one spin in four pays, but many of those wins are smaller than the stake: a $1 spin that pays $0.40 counts as a hit and still loses $0.60.
Max win and its odds
Max win is the cap on what one spin, including any bonus it triggers, can pay, usually given as a multiple of the bet. At a $1 bet, a 10,000x max win is $10,000. When a round reaches the cap, it ends there.
Some providers publish the odds of reaching the max win in the game's rules. For high-volatility slots they are often one in several million spins or longer. The max win exists, but it isn't something to plan around.
Why one slot can pay differently at two casinos
Many providers release each slot in several RTP versions, for example 96.5%, 95.5%, 94.5% and lower, and each casino chooses which one to run. The game looks the same in every version; only the maths changes. Over 1,000 spins at $1, the gap between 96.5% and 94.5% is $20 in average losses.
To check the version you are playing, open the game's rules or paytable once it has loaded at your casino: it should state the RTP. Review sites often quote the highest version, which may not be the one in front of you.
Bonus buy RTP
Slots with a bonus buy usually state a separate RTP for it, often close to the base game's. It applies to the price you pay: a $100 buy on a slot whose buy RTP is 96.3% returns $96.30 on average, however exciting the round looks. Buying doesn't beat the edge; it spends more money faster. Bonus buys aren't offered at casinos licensed in Great Britain. For how streamers use them, see what is a bonus hunt.
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FAQs
What is a good RTP for a slot?
Many online slots run at about 96% in their highest version, and a higher RTP means a lower average cost per spin. Over a single session, though, volatility matters far more than a difference of one or two percentage points.
Does a higher RTP mean I will win?
No. An RTP below 100% means the slot keeps part of every stake on average, whatever the figure. A 97% slot costs $3 per $100 staked on average instead of $4, but any single session can still end well up or well down.
Is high or low volatility better?
Neither pays more on average if the RTP is the same. Low volatility gives steadier, smaller wins and makes a budget last longer; high volatility gives long quiet spells and occasional big bonuses. Choose the one that suits your budget and patience.
Can a casino change a slot's RTP?
A casino can choose which RTP version of a slot to run, from the versions the provider offers. It can't change the maths of a version, which the provider sets and, in regulated markets, has tested before release. Check the RTP in the game rules.