Usage statistics

Usage statistics are collected whenever a user starts calibre. Every calibre installation has a unique 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.

Active installs: 2,855,441 (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):

	Spain	12.4%
	United States	11.7%
	Germany	9.2%
	China	7.8%
	France	6.2%
	Italy	6.2%
	United Kingdom	4.1%
	Canada	3.4%
	Netherlands	3.0%
	Poland	2.8%
	Russian Federation	2.3%
	Brazil	2.1%
	Australia	1.9%
	Argentina	1.5%
	India	1.5%
	Japan	1.2%
	Hungary	1.1%
	Mexico	1.1%
	Czech Republic	1.1%
	Austria	1.0%
	Belgium	1.0%
	Turkey	0.9%
	Ukraine	0.8%
	Switzerland	0.8%
	Taiwan, Province of China	0.8%
	Unknown	0.7%
	Romania	0.6%
	Bulgaria	0.6%
	Chile	0.5%
	Viet Nam	0.5%

% of unknown IP addresses: 0.7%

Most popular versions (Top 20):

4.2.0	12.1%
4.5.0	10.3%
4.3.0	9.5%
4.1.0	5.7%
4.4.0	5.5%
3.48.0	5.1%
3.46.0	4.6%
3.44.0	3.3%
3.40.1	2.5%
3.42.0	2.1%
3.39.1	1.9%
3.47.1	1.7%
3.34.0	1.6%
4.0.0	1.4%
3.36.0	0.9%
3.37.0	0.9%
3.31.0	0.8%
3.38.1	0.8%
3.28.0	0.8%
3.45.2	0.8%

Operating systems calibre runs on

win	82.3%
osx	15.0%
oth	2.7%