What are wildcard SSL certificates?

Luca Spiller
Head of Engineering
September 12, 2023

Today SSL certificates have become an essential tool in ensuring a website's trustworthiness and secure data transfer. Among the many types of SSL certificates available, wildcard SSL certificates stand out due to their unique ability to secure multiple subdomains with a single certificate. This article will delve into the world of wildcard SSL certificates, providing you with everything you need to know about their features, benefits, and use.

Understanding Wildcard SSL Certificates

A wildcard SSL certificate provides the flexibility to secure an unlimited number of subdomains on a single domain name. A standard SSL certificate secures only one fully qualified domain name. However, a wildcard SSL certificate, represented by an asterisk (*), can cover any subdomain associated with the domain, saving you the hassle and costs of managing multiple SSL certificates.

Benefits of Wildcard SSL Certificates

Wildcard SSL certificates offer numerous advantages that can significantly enhance a website's security and management. These benefits include:

  1. Cost-effectiveness: Instead of buying individual SSL certificates for every subdomain, a single wildcard SSL certificate can cover all of them, reducing expenses.
  2. Simplified Management: Managing multiple SSL certificates can be time-consuming and complex. With a wildcard SSL certificate, you only need to track, renew, and manage one certificate.
  3. Scalability: As your business grows and you add more subdomains, a wildcard SSL certificate can effortlessly accommodate the expansion, providing security for all new subdomains.

How Wildcard SSL Certificates Work

Wildcard SSL certificates work on the principle of public key infrastructure (PKI). When a wildcard SSL certificate is installed on a server, every subdomain connected to that server is automatically secured. The certificate uses an asterisk (*) in the common name field to represent any valid subdomain. For example, a wildcard SSL certificate for *.mycompany.com would cover login.domain.com, shop.domain.com, blog.domain.com, and any other subdomain, without needing individual certificates for each.

The functionality of Wildcard SSL certificates pivots around this asterisk — a wildcard character — that represents and secures any potential subdomain of the main site. This approach not only simplifies the management of SSL certificates for businesses with multiple subdomains but also proves to be a cost-effective solution.

As a single Wildcard SSL certificate is valid for any new subdomains, it alleviates administrative overhead. It’s a straightforward, efficient way to ensure that every nook and cranny of a website is encrypted and safe from prying eyes.

Choosing the Right Wildcard SSL Certificate Provider

When it comes to choosing a wildcard SSL certificate provider, there are several factors to consider:

  • Reputation: Choose a provider known for their reliability and good customer service. Look for online reviews and ratings to assess the provider's credibility.
  • Price: While cost-effectiveness is a significant advantage of wildcard SSL certificates, prices can vary among providers. Compare pricing plans and choose one that offers the best value for your money.
  • Customer Support: Opt for a provider that offers robust customer support to assist you with any issues or queries related to your wildcard SSL certificate.

Is Wildcard SSL Worth It?

Deciding whether a wildcard SSL certificate is worth the investment largely depends on your organization's specific needs and security stance. On one hand, wildcard SSL certificates offer a cost-effective and efficient solution for securing multiple subdomains under a single domain.

This not only simplifies certificate management but also ensures that any new subdomains are automatically protected, eliminating the need for additional purchases or installations.


Wildcard SSL certificates are a powerful tool for securing multiple subdomains under a single domain. They provide cost-effectiveness, easy management, and scalability, making them an ideal choice for businesses with multiple subdomains. By understanding their working mechanism and choosing the right provider, you can leverage their benefits to enhance your website's security and performance.