Types of SSL (Secure Sockets Layer) Certificates | What, Why & How

With the cyber crimes increasing at supersonic speed, it becomes crucial to be aware of different types of SSL Certificates available out there and which one is suitable for your company.

Without an SSL Certificate, your client’s data is transmitted over the wire unencrypted. Is that an acceptable risk?

Well, I don’t think so.

Surprisingly, there are still a lot of giant websites which are still not using SSL Certificates according to a recent Google report.

Therefore, before jumping directly onto the types of SSL certificates, let’s explore what and why of these certificates.

What are SSL Certificates & Why You Need Them?

SSL (Secure Sockets Layer) Certificates are small data files that digitally bind a cryptographic key to an organization’s details.

SSL Certificates Secure:

  1. Credit card transactions
  2. Data transfers
  3. Logins
  4. Social media sites browsing

Google is forcing websites to have SSL Certificates since their top priority is security. Therefore, if you have an updated SSL Certificate, they will simply love you.

Useful Abbreviations:

  1. SSL: Secured Sockets Layer
  2. CA: Certificate Authority
  3. DV: Domain Validation
  4. OV: Organization Validation
  5. EV: Extended Validation
  6. CSR: Certificate Signing Request

Different Types of SSL Certificates:

Now that you know not having an SSL Certificate could be disastrous, there are different types of SSL Certificates available:

They can be grouped based on:

  1. Validation level
  2. Number of secured domains/subdomains

On Validation Levels:

  1. Domain Validation Certificates
  2. Organization Validated Certificates
  3. Extended Validated Certificates

Under Number of Secured Domains/hostnames:

  1. Single Domain
  2. Wildcard
  3. Multi-domain

Types of SSL Certificates by Validation Level:

Certificate authorities issue certificates to organizations only after their identities have been validated.

Motive: To ensure we know who we are connected to when we send private information.

1. Domain Validation:

>> Level of Validation

>> How it is verified
The Certificate Authority or CA simply verifies that the organization has control over the concerned domain.

>> Mode of verification
Usually done via email. For verification, you either make changes to a DNS record or upload a file supplied by the CA to the domain. By demonstrating control over the domain, they will be issued a certificate.

>> Time taken 
Few minutes to few hours.

>> Validation expense
Minimal since there is no human involvement.

>> Indication
A browser with a secured HTTPS connection.

2. Organization Validated SSL Certificates

>> Level of Validation

>> How it is verified
The CA investigates the organization making the application though not very deeply. They will contact the organization to make sure it is authenticated.

>> Mode of verification
The Certificate Authority validates the ownership of the domain along with organization information included in the certificate like name, city, and country.

>> Time taken
Few days.

>> Validation expense
More than domain validation since humans are involved.

>> Indication
Display company information in certificate details.

3. Extended Validation Certificate:

>> Level of Validation
Most strict level.

>> How it is verified
The CA validates the ownership, organization information, physical location, and legal existence of the company. It also validates if the organization is aware of the SSL certificate request and then approves it.

>> Mode of verification
Documents are required to certify the company identity along with lots of checks.

>> Time taken 
Few weeks.

>> Validation expense
Most expensive due to high human involvements.

>> Indication
A green address bar with the company’s name.

Types of SSL Certificates by Number of Domains:

On the basis of the number of domains and subdomains, there are 3 certificates:

1. Single-name SSL Certificates:

Protects a single subdomain/hostname.

Example: If you purchase single-name SSL Certificate for www.techofworld.com, it doesn’t mean you can secure mail.techofworld.com.

2. Wildcard SSL Certificates:

Protects an unlimited number of subdomains for a single domain.

Example: If you purchase a certificate for www.techofworld.com, it will secure career.techofworld.com, help.techofworld.com, etc.

It will work on any subdomain. However, it will not secure abc.pro.techofworld.com.

3. Unified SSL Certificates/Multi-Domain SSL Certificates/SAN Certificates:

It allows customers to protect up to 100 domains with the help of the same certificate.

They are specially designed to secure Microsoft Exchange and Office Communications environments.

It protects different domains with a single certificate with the help of the SAN extension.

Self-Signed Certificates:

Other than these private CA issued SSL certificates, there is an option of self-signed certificates too.

What is a Self-Signed Certificate?

A certificate that will be signed by the person creating it, for example, website owner rather than a trusted authority.

Although these certificates offer the same level of encryption, you must not use them when you have anonymous visitors connecting to your website.


  1. This is because a visitor’s connection could be hijacked.
  2. The certificate cannot be revoked as a trusted certificate can.

Since an attacker can create a self-signed certificate, I don’t recommend it for public use.

It is a viable choice only for private use. It is better to spend a few bucks and go for a reliable SSL Certificate provider.

How Can I Evaluate My Needs Against Different Types of SSL Certificates?

SSL Certificates are always a good investment, however, by analyzing your business needs you can make a better choice.

Some of the questions you need to ask yourself before buying one are:

  • How many domains do I need to secure?
  • What type of website do I need to secure?
  • How important you think your customer’s trust is?

After you have decided on the basics, you need to set a budget. (Well, the most important thing)

Since the requirements of certifications vary from instant insurance, cheap price (DV Certificates), to highly pricey and strict business validation (EV SSL Certificates); you must decide considering your business location, documents, budget, etc.

Don’t compromise and make a rational decision when it comes to complete business security solution.

Note: You can read more about encryption service reviews and make a decision about which encryption service to use for your business.

How to Choose an SSL Certificate Provider?

Some of the factors that impact the choice of a client are:

  1. Brand
  2. Validation Type
  3. Issue Time
  4. Domains Included
  5. Server Licensing
  6. Installation Checker
  7. Supported Browsers
  8. Compatibility with mobiles
  9. Support for Scan
  10. Site Seal
  11. Trust Level
  12. Warranty

How Can I Install an SSL Certificate?

  1. Host with a dedicated IP address
  2. Buy a certificate
  3. Activate the certificate
  4. Install the certificate
  5. Update your site to using HTTPS