Methodology
How we rate slots
Every number on WildmarkSlots comes from a named public source, and every score is a formula you can check by hand. This page shows the formula, the sources and what the data does not cover.
What we measure
A slot page on WildmarkSlots is built from facts that the game studio publishes. We do not play-test games to estimate their numbers, and we never fill a missing field with a guess: if a value is not published, the page says so.
- RTP
- Return to player: the share of all money wagered that the game pays back over a very long run. 96% RTP means 96 back per 100 wagered on average, across millions of spins. A single session can end far above or below that.
- RTP versions
- Many studios ship the same game at several RTP settings and the casino picks one. We list every version the source records and show the highest as the headline. See RTP versions below.
- Volatility
- How unevenly a game pays: low volatility means frequent small wins, very high volatility means long dry runs and rare large wins. We show the studio's own label.
- Max win
- The largest win the game can pay on one spin or bonus round, as a multiple of the bet.
- Hit frequency
- The share of spins that return any win, as published by the studio. A win can be smaller than the bet.
- Mechanics
- Reels and rows, the win system (paylines, ways, cluster pays, Megaways) and features such as free spins, tumbling reels or a bonus buy.
The value score
The value score rates how generous a game's published numbers are for the player, from 0 to 10. It is the same formula for every game and nobody can pay to change it.
RTP part = (headline RTP − 90) ÷ 7.5, kept between 0 and 1
Max win part = (log10(max win) − 2) ÷ (log10(50,000) − 2), kept between 0 and 1
Value score = 10 × (0.7 × RTP part + 0.3 × Max win part)In words: 90% RTP or lower scores nothing on the RTP part and 97.5% or higher scores full marks. Max win counts on a logarithmic scale, so 100× scores nothing, about 2,200× scores half and 50,000× or more scores full marks. RTP carries 70% of the weight because it decides what a session costs on average; max win carries 30% because it decides how big the best outcome can be.
When a studio does not publish a max win, the max win part uses a neutral 5,000×, close to the catalogue median. Missing data then neither lifts a game to the top nor sinks it: a game with a 98% RTP and no published max win cannot outrank one with the same RTP and a published 50,000×.
Worked example: Starburst
Starburst by NetEnt has a headline RTP of 96.08% and a max win of 800×.
RTP part = (96.08 − 90) ÷ 7.5 = 0.811
Max win part = (log10(800) − 2) ÷ 2.699 = 0.335
Value score = 10 × (0.7 × 0.811 + 0.3 × 0.335) = 6.7Why the headline RTP and not the lowest version
The source records RTP versions for some studios only. Scoring the lowest version would punish exactly the studios that are open about their versions and reward the ones whose versions are not recorded. Every slot page shows the lowest recorded version next to the score, so you can see the worst case yourself.
What the score ignores
Theme, graphics, sound, bonus features and how fun a game feels are not in the score. They matter, but they are taste, not data. Use the score to compare the maths of games you already like, not to pick a game for you.
RTP versions
A studio can certify one game at several RTP settings, for example 96.2%, 94.2% and 91.2%. The casino chooses which version to run, and the game looks the same in every version. Over 1,000 wagered, a 96% version loses 40 on average and a 91% version loses 90: more than twice as much for the same game.
WildmarkSlots shows every recorded version on the slot page with the cost of each per 1,000 wagered. We cannot tell which version a particular casino runs. Most games show their RTP in the paytable or help screen: check it before you play.
Where the data comes from
RTP, volatility, max win, release year
Slot RTP Database by toolsgambling.com (version 1.0.12, frozen 28 September 2026), licensed under Creative Commons Attribution 4.0. Each record links to the studio's own game page, and every WildmarkSlots slot page links to that official page too. We normalised game and studio names, merged duplicate records and computed the derived figures on this site (value score, percentiles, cost per 1,000 wagered).
Mechanics and features
slot-mechanics-dataset by stepupgaming, licensed under the MIT licence: reels, rows, win system, hit frequency and features for the games it covers. We use its data only, not its images.
Coverage
Share of the 3,708 slots in the catalogue with each field. Gaps are gaps in what studios publish and what the sources record; we show them rather than hide them.
| Field | Slots with it | Note |
|---|---|---|
| Headline RTP | 100% | Every game in the catalogue has one. |
| Several RTP versions | 20% | Recorded for 4 studios: Hacksaw Gaming, Play'n GO, Push Gaming and Yggdrasil. |
| Volatility | 77% | As the studio labels it. Labels are not standardised between studios. |
| Max win | 34% | As a multiple of the bet. |
| Release year | 56% | – |
| Hit frequency | 19% | – |
| Mechanics and features | 8% | Reels, rows, win system, free spins, bonus buy and similar. |
Catalogue medians, for context on any single game: headline RTP 96.14%, max win 5,250× (of 1,256 slots with a published max win).
Images and demos
Game artwork and playable demos belong to the studios. WildmarkSlots shows a cover or a demo only when it comes from a licensed media service; until then a slot page shows a generated pattern cover, clearly not game art, and links to the official game page.
Independence
- WildmarkSlots does not link to casinos, runs no affiliate links and has no paid placements. No game ranks higher for money.
- Scores come from the formula above. Editors cannot set a score by hand, and the same rule applies to every studio.
- There are no accounts and no real-money play on WildmarkSlots. Demos, where available, use play money only.
Corrections
Found a number that does not match the studio's official game page? Send us the game and a link to the official page through the contact form. We check the studio's own page and correct the record. The data is also refreshed from the sources on every catalogue update.