Action hooks online listings

The WordPress Codex (https://codex.wordpress.org/) and WordPress Code Reference (https://developer.wordpress.org/reference/) are documentation sites that contain a multitude of information that is useful to users and developers alike. When it comes to action hooks, the Codex contains information on the most commonly used hooks, with basic descriptions indicating how they can be used, and can be found here: https://codex.wordpress.org/Plugin_API/Action_Reference. That being said, this is not a complete listing.

There are many third-party sites that parse the WordPress source code and provide their own hook listings (for example, http://hookr.io). While hooks are not as eloquently documented in these types of raw listings, they do provide basic information on their names and where they are called as WordPress generates pages for visitors and administrators. These details can be enough to find a hook based on the functionality that you are trying to implement.