Hunter visits the whole web to collect email addresses.
When you search a website on Hunter, it returns all the email addresses using the same domain (i.e. finishing with @company.com) we found on the web. The URLs where the email addresses were found and the date they were found are also returned in the search.
Hunter constantly updates its emails. As soon as our crawlers find new publicly available emails, they are added to our database. When emails are removed from websites, they are also removed or edited in Hunter.