What is a Double Wildcard SSL Certificate?

1 Star2 Stars3 Stars4 Stars5 Stars (1 votes, average: 5.00 out of 5)
Double Wildcard SSL Certificate

About Double Wildcard SSL Certificate and How to Secure Multi-level Subdomains

So, let me be clear; you landed on this page as you want to enquire about a Double Wildcard SSL certificate. I think that you must need it to secure multi-level subdomains, right?

But what if I tell you there is no such thing as a Double Wildcard SSL certificate? Don’t get shocked, but it’s 100% correct. It’s just a myth (I think started by some SSL noob!) that many of us believe to be accurate and, thus, trying to gather information regarding this certificate so that they can use the certificate to secure their multi-level subdomains.

But in the end, you still need to get the answer to the main problem, which I hope is the same as what I am thinking – How to secure multi-level subdomains? Before answering this query, let’s try to understand the answer to a related question – Why can’t we use Wildcard Certificate to secure multi-level subdomains? Once you apprehend this, everything will be like a cherry on the pie, ready to be picked – A simple task.

Why can’t we use Wildcard Certificate to secure multi-level subdomains?

To be precise and to the point, it is because of a single reason – the way a URL is structured. A URL structure consists of three parts:

  • Subdomains
  • Domains
  • TLD (Top-level domain)

Most websites have subdomains at a single level, and they separate subdomains using dots or periods (.) But there can be subdomain levels beyond that, such as company.mail.domain.com or employees.login.domain.com.

The problem occurs when a website has subdomains at multiple levels. Securing each subdomain becomes incredibly challenging, as an SSL Wildcard Certificate can only secure multi-level subdomain and their subdomains.

For example, domain.com can secure the following:

  • www.domain.com
  • xyz.domain.com
  • Doublessl.domain.com

Note: Wildcard Certificates are best to secure first-level subdomains.

But, if you are wealthy enough, you can solve this issue by buying a separate SSL Wildcard certificate for each multi-level subdomain name.

For example, .xyz.domain.com can’t secure the following domains:

  • domain.com
  • www.domain.com
  • Blog.domain.com

This is because a single Wildcard SSL certificate can or will only secure that multi-level subdomain and its subdomains. Hence, it can’t secure the domain mentioned above, but it sure can secure these domains:

  • www.xyz.domain.com
  • wildcard.xyz.domain.com
  • Doublewildcard.xyz.domain.com

How to secure multi-level subdomains?

If there are multi-level subdomains or multiple domains with their sub-domains, then in that case, you can use – Multi Domain Wildcard SSL Certificate.

This SSL certificate is capable of securing multi-level sub-domains of multiple domains with a single SSL certificate on the single certificate signing request (CSR) as it uses wildcard SANs. The certificate authority validates the domain ownership, rather than going through a lengthy process, to obtain a Multi Domain Wildcard SSL. As a result, they can issue the certificate within a few minutes.

It also contains the premium SSL encryption features such as 256-bit RSA encryption, unlimited server licenses, FREE unlimited reissuances, website trust seal, and up to 247 additional SANs.


When securing a website with multiple subdomains, a common misconception is the existence of a Double Wildcard SSL Certificate. While a Double Wildcard SSL Certificate does not exist, website owners can still secure multi-level subdomains with a Multi Domain Wildcard SSL Certificate.

Janki Mehta

Janki Mehta is a Cyber-Security Enthusiast who constantly updates herself with new advancements in the Web/Cyber Security niche. Along with theoretical knowledge, she also implements her practical expertise in day-to-day tasks and helps others to protect themselves from threats.

Buy Cheap Wildcard SSL