• Alexa – shows traffic trends for competing websites. Alexa has a heavy webmaster bias that is nowhere near as noticeable at Compete or Quantcast. Here is an in-depth Alexa review & you can download a list of their top 1,000,000 websites.
  • Quantcast – shows site traffic and demographic trends and details. Also allows you to download a list of their top 1,000,000 websites.
  • Google Trends for Websites – free tool from Google showing traffic estimates, visitor country location, top 10 related websites, and top 10 related keywords. Only returns data for fairly high traffic websites though. Google also offers an Ad Planner, but it only shows data for sites in the Google display network.
  • NetPeak Checker – desktop software which pulls in market research data from various 3rd party sources.
  • URL Profiler – a similar service to NetPeak, which is a paid product & pulls in more data sources.
  • SeoTools for Excel – free Excel spreadsheet with many SEO-related features baked into it.
  • 90 DataGrabber – Excel spreadsheet which interfaces with the Majestic & SEMRush APIs to pull in competitive research data. Overview video here. While it is free, it requires you to have paid accounts at Majestic or SEMRush to fully use it.
  • SEOGadget for Excel – another Excel-based suite of SEO tools.
  • RankTank – a collection of Google Drive / Google Docs spreadsheets for common SEO functions like rank checking. There is also a simple SEO audit tool based on Google Docs.
  • Archive.org – see how old a website is & what it looked like in the past.
  • DomainTools – see Whois data and how many times a domain has changed hands.