If you’re a plugin developer, you know how difficult it can be to figure out which hooks are available. This WordPress hooks database automatically scans each WP build for apply_filters() and do_action() to figure out exactly which hooks are available in each version.
What is this good for?
- See what new hooks are available with each new version of WordPress
- See which hooks have been deprecated (use the “view all hooks” option)
- Easily learn exactly which WP file(s) use each hook. That way, if the hook is poorly documented, you can just look in the source and figure out what it does.
What is this not good for?
The goal is not to explain what each hook does, but rather to list which are available in each version. If you just want to know what a hook does, check out the official action reference 
and filter reference , as well as the information at flat earth .
That being said, you’ll notice that those sites fail to include all the hooks. When that’s the case, find the hook here. This site will tell you where in the WP source the hook is applied, making it easy for you to figure out what it does on your own.