The Webalizer - The Webalizer is a fast, free web server log file analysis program.
KeywordTool.io - KeywordTool.io is the best FREE alternative to Google Keyword Planner and Ubersuggest. It uses Google's autocomplete feature to get over 750+ long-tail keywords for any given query.
Matomo - Matomo is an open-source web analytics platform
Google Trends - Explore Google trending search topics with Google Trends.
AWStats - AWStats is a Open Source Web Analytics software written in Perl.
Keywords Everywhere - Free browser add-on for keyword volume, CPC & competition