You can add unlimited websites to track in Matomo (Piwik), in the Admin Websites section. In fact, Matomo scales well to thousands of websites, and a few Matomo users are tracking even more. Each Website is defined by a URL. You can track sub domains in the same Matomo website, or you can create a different website for some of your subdomains. Learn more about creating Websites in the Managing websites page.

The ‘All Websites’ dashboard is a useful first page to look at for a quick overview of the performance of all your websites over the last day or week. You can even make it your default page to load in Matomo (go to top menu Administration > Personal > Settings). If you track more than 10 websites, the Website selector will display the first ten sites only, and show a search field where you can search quickly to look at another website.

When you want to group together the data and reports from multiple websites’ domain names into the same website in Matomo, you have two solutions:

  1. you can setup Cross Domain linking in Matomo to ensure that your visitors will be accurately tracked across domains into the same visit. Learn how to setup cross-domain tracking in our FAQ How do I accurately measure a same visitor across multiple domain names?
  2. you can create a new Roll-Up and group the websites together. Roll-up reporting lets you aggregate the reports of multiple websites you select into a Roll-Up. You can create an unlimited number of Roll-ups. Learn more in the Roll-Up reporting user guide.

Other important notes:

  • When tracking user across multiple websites, it is generally important to configure First party cookie domains in the Javascript Tracking code (for better data accuracy). Learn more in the page Measuring domains and/or sub-domains.
  • If you track many subdomains in the same Matomo website, you might want to see the domain name directly in your Page Title reports. If you want to show “support.example.org/Homepage” instead of simply “Homepage”, check out the JS setDocumentTitle documentation.
  • In the Admin Websites page, you can also define for each website a list of Alias URLs which contains all the other domains and subdomains that will be tracked. This will ensure they don’t appear in your “Referrer” reports.
  • The official Matomo Mobile App supports all these reports, including the ‘All Websites’ dashboard.
  • Sometimes you have only one website or app and it includes multiple “sections” (or page “categories” or “mini-site” or “multi-tenants”), and you want to track and report them separately from each other. For example your website is translated in multiple languages, and you want to see reports for each language or market (“section”). Learn more in this FAQ
  • See also: Install Matomo on one server and track visits on websites that are hosted on other servers.