RTP is easy to quote and hard to feel. Enter your stake, a slot’s RTP and a number of spins to see what it costs, on average, to play — the honest maths behind the numbers.
This is a long-run average, not a session forecast — real sessions swing hard, and a rare big win or a long dry run are both normal. What never changes is the direction: with a house edge, the expected result is always a loss, and it grows the longer you play. There is no strategy that beats a random number generator. Set a budget, only play with money you can afford to lose — 18+. See games & odds and responsible gambling.
RTP (return to player) is the share of all stakes a game is built to pay back over the very long run. The gap to 100% is the house edge — the casino’s built-in margin. This calculator turns that percentage into pounds: your total stakes, the expected loss at that edge, and what you’d get back on average. It’s the same figure the operators design around, shown from your side of the screen.
Two honest caveats. First, it’s an average over huge numbers of spins — any real session can win or lose far more, which is what volatility describes. Second, the expected result is always a loss: no betting system, timing or “hot” machine changes a random number generator. Use it to set a realistic budget, not to plan a profit. If gambling stops being fun, see GAMSTOP & responsible gambling.
How do you work out the expected loss on a slot?
Multiply your total stakes by the house edge (100% minus the RTP). Betting £1 a spin for 500 spins stakes £500; on a 96% RTP slot the house edge is 4%, so the expected loss is about £20. You'd get back roughly 96% of your stakes on average — over the very long run.
Does higher RTP mean I'll win?
No. A higher RTP means a smaller expected loss over time, not a profit — the expected result is still a loss because the house edge is positive. RTP is a long-run average across millions of spins, not a guarantee for your session.
Why does the expected loss grow the more I play?
Because the house edge applies to every bet. The more you stake in total, the more the average result converges on that edge — so playing longer increases your expected loss. Short sessions are where big swings (up or down) happen; long sessions grind toward the maths.