What is the most used SEO tool?

Google Search Console is the most widely used SEO tool overall, simply because it is free, comes directly from Google, and is effectively required to monitor indexing and search performance for any site.

Among paid tools, Ahrefs and Semrush are the most commonly cited by SEO professionals for keyword research and competitor analysis, based on industry surveys run by Search Engine Journal and similar outlets in recent years.

The right answer depends on the job. Search Console for diagnostics, Ahrefs or Semrush for research, and a dedicated writing or publishing tool for actually producing content are three separate needs, not one tool.

For the content production piece specifically, an SEO automation platform picks up where research tools stop.