Usage statistics are collected whenever a user starts calibre. Every calibre installation has a randomly generated ID, this ID remains unchanged by upgrades and even an uninstall/re-install. This ID is used to collect usage statistics. Only this ID is stored, no other identifying information is collected. And no collected information is ever shared with any third party.
Active installs: 3,065,191 (those that have started calibre at least once in the last 60 days)
Note that installs are not users. A single user could run calibre on multiple computers. A single calibre install could be used by multiple people.
Installs by country (237 countries, top 30 shown):
|Taiwan, Province of China||0.9%|
% of unknown IP addresses: 0.0%
Usage share by major version
Most popular versions (Top 20):
Operating systems calibre runs on