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: 2,741,818 (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 (238 countries, top 30 shown):

	Spain	12.1%
	United States	11.9%
	Germany	9.5%
	China	7.8%
	France	6.3%
	Italy	5.9%
	United Kingdom	4.1%
	Canada	3.3%
	Netherlands	3.1%
	Poland	2.7%
	Brazil	2.4%
	Russian Federation	2.2%
	Australia	2.0%
	Argentina	1.7%
	India	1.5%
	Japan	1.1%
	Mexico	1.1%
	Hungary	1.1%
	Austria	1.0%
	Czech Republic	1.0%
	Belgium	1.0%
	Ukraine	0.8%
	Turkey	0.8%
	Switzerland	0.8%
	Taiwan, Province of China	0.8%
	Bulgaria	0.6%
	Chile	0.6%
	Romania	0.6%
	South Africa	0.5%
	Hong Kong	0.5%

% of unknown IP addresses: 0.5%

Most popular versions (Top 20):

3.42.0	17.7%
3.44.0	14.2%
3.40.1	7.9%
3.41.3	5.7%
3.39.1	4.3%
3.34.0	2.8%
3.43.0	2.5%
3.37.0	1.7%
3.36.0	1.7%
3.38.1	1.7%
3.31.0	1.6%
3.28.0	1.4%
3.33.1	1.3%
3.32.0	1.3%
3.35.0	1.2%
3.26.1	0.9%
3.30.0	0.9%
3.29.0	0.8%
3.23.0	0.8%
3.15.0	0.8%

Operating systems calibre runs on

win	81.9%
osx	15.5%
oth	2.6%