Most Popular Certificate Authorities

This section provides a list of most popular certificate authorities in 2009. The top is 'Go Daddy', which has about 21.17% of the market share.

Based on the Website monitoring report provided, top 12 CA (Certificate Authorities) in 2018 are:

CA               Share
IdenTrust        45.5%
Comodo           31.3%
DigiCert Group   11.0%
GoDaddy Group     6.9%
GlobalSign        3.1%
Certum            0.8%
Actalis           0.4%
Entrust           0.3%
Secom Trust       0.3%
Let's Encrypt     0.2%
Trustwave         0.1%
WISeKey Group     0.1%

Based on a research report from, top 30 certificate authorities in 2009 were:

 Share   Group                Certificate Authority
21.17%   Go Daddy   , Inc.
12.79%   VeriSign             Equifax Secure Inc.
11.19%   VeriSign             Thawte Consulting cc
10.58%   Comodo               UTN-USERFirst-Hardware
 8.23%   VeriSign             VeriSign, Inc.
 7.80%   VeriSign             Equifax
 6.38%   VeriSign             VeriSign Trust Network
 3.37%   Comodo               Comodo CA Limited
 2.55%   Network  Solutions   Network Solutions L.L.C.
 2.25%   Go Daddy             Starfield Technologies, Inc.
 1.57%                        DigiCert Inc
 1.24%   GlobalSign           GlobalSign nv-sa
 0.67%                        Cybertrust
 0.63%   AmbironTrustWave     SecureTrust Corporation
 0.60%   VeriSign             Thawte Consulting (Pty) Ltd.
 0.56%                        Root CA
 0.55%                        IPS Certification Authority s.l.
 0.47%   Comodo               Secure Business Services, Inc.
 0.42%   VeriSign             RSA Data Security, Inc.
 0.34%                        Betrusted Japan Co., Ltd.
 0.33%                        StartCom Ltd.
 0.30%                        SECOM
 0.27%   GlobalSign           Alpha
 0.25%   GlobalSign           GlobalSign
 0.24%                        TC TrustCenter for Security in Data ...
 0.23%                        CAcert Inc.
 0.20%   Comodo               Comodo Limited
 0.19%                        T-Systems Enterprise Services GmbH
 0.19%                        U.S. Government
 3.11%                        (Others)

Last update: 2018.

Table of Contents

 About This Book

Introduction of PKI (Public Key Infrastructure)

 What Is PKI (Public Key Infrastructure)?

 Usage Examples of Public Key Infrastructure

Most Popular Certificate Authorities

 Introduction of HTTPS (Hypertext Transfer Protocol Secure)

 Using HTTPS with Google Chrome

 Using HTTPS with Mozilla Firefox

 HTTPS with IE (Internet Explorer)

 Perl Scripts Communicating with HTTPS Servers

 PHP Scripts Communicating with HTTPS Servers

 Java Programs Communicating with HTTPS Servers

 Windows Certificate Stores and Console

 .NET Programs Communicating with HTTPS Servers - Root CA Offering Free Certificates

 PKI CA Administration - Issuing Certificates

 Comodo Free Personal Certificate

 Digital Signature - Microsoft Word

 Digital Signature - 3

 S/MIME and Email Security

 PKI (Public Key Infrastructure) Terminology

 Outdated Tutorials


 Full Version in PDF/EPUB