Smart External Link Click Monitor [Link Log]
This free Plugin for WordPress and ClassicPress allows you to track where your visitors leave to by monitoring clicks on external links
This handy little plugin allows you to track which external links your visitors click on. Data are stored on your server in your WordPress resp. ClassicPress database. No external service needed. No privacy concerns.

The plugin changes all your links to external sites when a post or page is displayed. When editing a post or page all links appear unchanged. There is no need to change anything.
To exclude multiple clicks from the same IP-address from counting the visitors IP-address has to be stored into the database. Because the IP-address is not needed for anything else it is encrypted before it is stored. The encrypted IP-addresses can not be decrypted. So this plugin does not store personal data in the sense of GDPR (see Plugin Privacy Information).