How this works & where the numbers come from
The model
Each game is simulated with a payout model calibrated so its long-run return exactly equals the RTP, with a volatility rating (1–10) shaping how streaky wins are. Tens of thousands of simulated sessions (Monte Carlo) estimate the chance of leaving ahead, optimal spins and walk-away targets. Statistical estimates of real behaviour, not a replica of any game's internal reel maths.
Player-Friendliness Score
0–100: 55% RTP-value + 45% best realistic chance of leaving ahead (rewards lower volatility). A comparison aid, not a safety rating — no score makes a game +EV.
RTP verification
Every verified figure is read from the game's own in-game rules/paytable panel on the operator's site, with the date recorded.
Operators run reduced-RTP versions and change them at any time — always confirm in-game. See the
Studios page for each game's theoretical ceiling and how far platforms fall below it.
Frequently asked questions
Do UK online casinos change a slot's RTP?
Yes. Studios ship several RTP versions and each casino picks one — often a lower one. The same game can pay about 96.5% at one UK casino and under 92% at another, and they needn't tell you which you're playing.
How do I find the real RTP of a slot?
Open the game's info/rules panel at your casino; on UKGC-licensed sites the deployed RTP is stated at the bottom of the rules. That figure — not the studio headline — is what you're actually playing.
What is a good RTP for an online slot?
Higher is better (smaller house edge), but no slot exceeds 100% RTP, so all lose over time. UK deployments are often 92–94% even when the studio ceiling is 96%+.
Can you win at online slots in the long run?
No. Because every slot returns under 100% of stakes, the expected result is a loss that grows more certain the more you play. The best any strategy does is lose slower or improve a single session's chance of finishing ahead.
What is the Player-Friendliness Score?
A 0–100 score blending deployed RTP (55%) with the volatility-aware chance of finishing ahead (45%). Higher means less-bad — never profitable.
Sources & verification log
Independence & legal
The Truth Machine is an independent, not-for-profit educational project,
not affiliated with, endorsed by, or connected to any gambling operator or game studio named here. It hosts no games, takes no bets, accepts no payment, carries no affiliate links. Operator and game names are trademarks of their respective owners, used for factual identification and comparison. Figures are presented in good faith as read on the stated date and may since have changed; information only, no warranty; not financial or gambling advice.
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