It is estimated that the average chance of catching a shiny Pokémon in the wild is approximately 1 in over 4000! It can take time to catch all them all and it may seem like we will never catch one because they are much less common. The good news is that the shiny rate during community day is 1 in 25!
There are a couple of websites that have documented their shiny catch rates for the curious minds.
thesilphroad.com: they also document that the base shiny rate is 1/500.
shinyrates.com: they list most Pokémon on their site.
We can check out our own shiny rate by taking a look at our pokédex. Many people will also “shiny check” without catching a Pokémon at the risk of missing out on specific IVs we want to catch.
Global Health And Wellness Institute 