EXHIBIT 21.1

List of Subsidiaries of

j2 Global, Inc.

j2 Global, Inc.'s principal affiliates as of December 31, 2018, are listed below. All other affiliates, if considered in the aggregate as a single affiliate, would not constitute a significant subsidiary.

Name	State or Other Jurisdiction of Incorporation
j2 Australia Cloud Connect Pty Ltd		Australia
j2 Global Australia Pty Ltd		Australia
j2 Global Canada, Inc.		Canada
j2 Global Denmark A/S		Denmark
Electric Mail (Ireland) Limited		Ireland
j2 Global Holdings Limited		Ireland
j2 Global Ireland Limited		Ireland
Ziff Davis Holdings Limited		Ireland
Ziff Davis Ireland Limited		Ireland
j2 Global (Netherlands) B.V.		Netherlands
NCSG Holding AB		Sweden
Stay Secure Sweden AB		Sweden
j2 Global UK Limited		United Kingdom
Livedrive Internet Limited		United Kingdom
Ziff Davis International Ltd.		United Kingdom
DW Prime Holdings Inc.		Delaware, United States
Ekahau, Inc.		Delaware, United States
Everyday Health, Inc.		Delaware, United States
Everyday Health Media, LLC		Delaware, United States
Humble Bundle, Inc.		Delaware, United States
IGN Entertainment, Inc.		Delaware, United States
j2 Cloud Services, LLC		Delaware, United States
j2 Web Services, Inc.		Delaware, United States
KeepItSafe, Inc.		Delaware, United States
Mashable, Inc.		Delaware, United States
Offers.com, LLC		Delaware, United States
OnTargetJobs, Inc.		Delaware, United States
SaleBuild, Inc.		Delaware, United States
ThreatTrack Security Holdings, Inc.		Delaware, United States
Ziff Davis, LLC		Delaware, United States
ThreatTrack Security, Inc.		Florida, United States
Prime Education, LLC		Florida, United States
MedPage Today, L.L.C.		New Jersey, United States
Excel Micro, LLC		Pennsylvania, United States
Ookla, LLC		Washington, United States