In general, real casinos tend to have about a 90% RTP rate: it means that for every dollar a user spends they are expected to receive about 90 cents. Online casinos are more generous: their RTP rate is usually higher than 94%, and the most giving websites even return about 97%. It doesn’t guarantee that you will always get an exact part of a deposit back: the factor of randomness is still prevalent, so it’s just a general number to help you to make an image of what to expect from a casino or a pokie.