What is a wildcard certificate?

A wildcard certificate can secure multiple subdomains under one unique domain name. A wildcard certificate can be recognised by the use of an asterisk, such as *.networking4all.com. This protects multiple underlying services, such as sip.networking4all.com or webmail.networking4all.com. It is also possible to install a wildcard certificate on multiple servers.

When ordering a wildcard certificate, it is important to keep subdomain levels in mind. This means that a wildcard certificate for *.networking4all.com will secure test.networking4all.com, but cannot work for test.webmail.networking4all.com. That requires a separate wildcard certificate.

Wildcard certificates are only available as domain validated (DV) or organisation validated (OV) certificates. It is not possible to order a wildcard EV certificate.

Wildcard SAN

A Wildcard SAN certificate offers the same functionalities as a regular wildcard certificate, but also allows the use of wildcards in the SAN names. The following example explains this:

Common name: www.networking4all.com
SAN1: dev.ssl.nu
SAN2: *.support.ssl.nu
SAN3: dev.ssl.be
SAN4: *.support.ssl.be

The Wildcard SAN certificate is only available as an OV certificate. This type of SAN certificate has space for up to 100 SAN names.

Unlike regular certificates, the wildcard SAN does not automatically include the domain name with www. If the domain name with www needs to be secured as well, it has to be added to the certificate as a separate SAN name. The common name is exempt from this rule: it is supported both with and without leading www.


Wildcard certificates and Wildcard SAN certificates can be requested through our SSL wizard.