How to compare slot providers
A studio’s catalogue says a lot about the games you will meet: some studios release hundreds of games with similar maths, others fewer games with very different volatility. Average RTP shows how generous a studio’s published numbers are overall; the median is less affected by a few unusual games.
RTP versions by studio
Several studios certify their games at more than one RTP and let casinos choose. For Hacksaw Gaming, Play'n GO, Push Gaming and Yggdrasil the open data records every version, so their game pages on WildmarkSlots show the full range. For other studios a single RTP is listed, which does not mean other versions do not exist.
Volatility
The most common volatility tells you the typical feel of a studio’s games. It is based on the labels studios publish; where a studio publishes few labels, the comparison is less reliable, and the provider page says how many games have one.