An SSL certificate is essential for every website these days. It ensures data is transmitted encrypted between your visitors and your website. In this guide we explain what SSL is, why you need it, and how to install it.

What is an SSL certificate?

Technically, TLS (Transport Layer Security) is used nowadays, the successor to SSL. However, the term SSL is still the most widely used, so we also refer to SSL in this article.

How does SSL work?

When a visitor opens your website, the following happens:

1. The browser asks the server to identify itself
2. The server sends a copy of the SSL certificate
3. The browser checks whether the certificate is valid
4. If everything checks out, an encrypted connection is set up

This entire process takes only milliseconds and is invisible to your visitors.

Why is SSL important?

Data security

Without SSL, data is sent as plain text. Anyone intercepting the traffic can read along. Think of:

• Login credentials and passwords
• Credit card numbers and payment details
• Personal information in forms
• Chat messages and email addresses

With SSL, this data is encrypted and unreadable to third parties.

SEO benefits

Google uses HTTPS as a ranking factor. Websites with SSL rank higher in search results than websites without. This has officially been Google's policy since 2014.

Visitor trust

Browsers now actively warn about websites without SSL. Chrome shows "Not secure" in the address bar. This scares visitors off and can lead to:

• Higher bounce rates
• Fewer conversions
• Damage to your reputation

Legal requirements

The GDPR requires you to take appropriate technical measures to protect personal data. SSL is one of those measures. Without SSL you risk fines.

Types of SSL certificates

Domain Validation (DV)

This is the basic level. The certificate authority only checks whether you own the domain. Verification happens via email or a DNS record.

Characteristics:

• Fast issuance (minutes to hours)
• Lowest price or free (Let's Encrypt)
• Suitable for blogs, portfolios, and small websites
• Only shows a padlock, no company name

Organization Validation (OV)

With OV, your organization is also checked. The certificate authority verifies that your company exists and is legitimate.

Characteristics:

• Issuance takes 1-3 days
• Typically costs 50-200 euros per year
• Suitable for company websites and webshops
• Shows company details in certificate details

Extended Validation (EV)

The highest validation level. Extensive checking of your organization, including legal entity and physical address.

Characteristics:

• Issuance takes 1-2 weeks
• Costs 200-1000 euros per year
• Suitable for banks, large webshops, and financial institutions
• Used to show a green bar (no longer in modern browsers)

Comparison of SSL types

Feature	DV	OV	EV
Validation	Domain	Domain + organization	Extensive
Issuance time	Minutes	1-3 days	1-2 weeks
Price	Free - 50 euros	50-200 euros	200-1000 euros
Suitable for	Blogs, small sites	Companies, webshops	Finance, enterprise

Let's Encrypt vs paid certificates

Advantages of Let's Encrypt

• Free - No annual costs
• Automatic renewal - No hassle with manual renewal
• Easy installation - Activated with one click at Theory7
• Reliable - Recognized by all browsers
• Same encryption - Just as strong as paid DV certificates

When do you choose paid?

A paid certificate has added value in these situations:

• You want OV or EV validation for extra trust
• You need a warranty
• Your customers expect a specific certificate brand
• You have multiple subdomains (wildcard certificate)

For most websites, Let's Encrypt is more than enough.

Installing an SSL certificate

Installing SSL at Theory7

At Theory7, installing SSL is simple:

1. Log in to DirectAdmin
2. Go to SSL Certificates
3. Click on Let's Encrypt SSL
4. Check your domain(s)
5. Click on Save

Your certificate is active within a few minutes. Renewal happens automatically every 60 days.

Installing SSL via cPanel

In cPanel you'll find SSL under Security → SSL/TLS. Most cPanel installations also have AutoSSL for free Let's Encrypt certificates.

Setting up WordPress for HTTPS

After installing your SSL certificate you need to configure WordPress:

1. Go to Settings → General
2. Change WordPress Address to https://
3. Change Site Address to https://
4. Save

Use a plugin like Really Simple SSL to automatically fix mixed content.

Common SSL problems

Mixed content warnings

This happens if your website still loads some resources (images, scripts) via http. Solution:

• Find and replace http:// with https:// in your database
• Check hardcoded URLs in your theme
• Use the developer tools to find problematic resources

Expired certificate

Let's Encrypt certificates are valid for 90 days. At Theory7 they're renewed automatically. With other providers you sometimes have to do this manually or set up a cron job.

Redirect loops

Sometimes an infinite redirect between http and https occurs. Check:

• Your .htaccess rules
• WordPress URL settings
• Cloudflare or CDN settings

Summary

At Theory7 you get free Let's Encrypt SSL with every hosting package. Installation takes a few clicks and renewal happens automatically. That way you can focus on your website instead of certificate management.

Do you have questions about SSL or is installation not working? Our support team is happy to help.

Frequently asked questions about an SSL certificate

What does an SSL certificate cost?

The cost of an SSL certificate varies widely. A basic Domain Validation (DV) SSL certificate is often already available for free via Let's Encrypt. Paid variants with Organization Validation (OV) or Extended Validation (EV) cost between 50 and 500 euros per year, depending on the provider and type of validation. For a professional web hosting environment, a paid SSL certificate is often the better choice because of the extra guarantees and the trust it conveys.

How long is an SSL certificate valid?

Most SSL certificates are valid for a maximum of 13 months (397 days). Let's Encrypt certificates are valid for 90 days but are renewed automatically. It's important to renew your SSL certificate on time, because an expired certificate causes warning messages in the browser and can scare off visitors. Many hosting providers offer automatic renewal.

SSL certificate and SEO benefits

Google has officially confirmed that HTTPS is a ranking factor. Websites with a valid SSL certificate therefore rank better in search results. Chrome also shows a padlock icon for secure connections, which increases visitor trust. For a domain name you want to take seriously, an SSL certificate is therefore essential.

Wildcard and Multi-Domain SSL certificates

Managing multiple subdomains? Then a wildcard SSL certificate is an efficient solution. This type of SSL certificate secures both the main domain and all subdomains (for example shop.example.com, blog.example.com). For organizations with multiple domain names there's also a Multi-Domain or SAN SSL certificate, which lets you secure up to 250 different domains with one certificate.

Whether you run a small blog or manage a large webshop hosting environment, an SSL certificate is an absolute necessity these days. Take your website's security seriously and choose the SSL certificate that fits your situation.

SSL certificate installation step by step

Solving common SSL certificate errors

After installing your SSL certificate you may run into problems such as mixed content warnings, where some elements on your page are still loaded via HTTP instead of HTTPS. Check all internal links, scripts, and stylesheets to make sure everything is requested via HTTPS. Another common mistake is an expired SSL certificate, which you can prevent by setting up automatic renewal with your hosting provider.

SSL certificate and e-commerce

For webshops, an SSL certificate is not just desirable but legally required. The GDPR and PCI DSS standards require that all personal data and payment data be transmitted encrypted. An SSL certificate ensures credit card numbers, addresses, and passwords are sent safely over the internet. Without a valid SSL certificate, most payment providers also refuse to link their services to your webshop, meaning you simply can't receive online payments.

Finally, it's wise to regularly check your SSL certificate using online tools such as SSL Labs. These tools analyze your SSL certificate's configuration and give a security score. Any vulnerabilities become immediately visible, so you can fix them quickly.

Invest in an SSL certificate today and give your visitors the trust they deserve when visiting your website.

SSL Certificate Types and Validation Levels

Domain Validation (DV)

A Domain Validation certificate is the most basic type and only verifies that you own the domain. Validation happens automatically, usually via email or a DNS record, and the certificate is issued within a few minutes. DV certificates are ideal for personal websites, blogs, and small business sites. Let's Encrypt offers free DV certificates that can be renewed automatically. The downside is there's no company information in the certificate, so visitors can't verify who is behind the website.

Organization Validation (OV)

With an Organization Validation certificate, not just domain ownership is verified, but also the existence and identity of the organization. The certificate authority checks company details with the Chamber of Commerce or a similar body. This process takes a few business days. OV certificates are suitable for business websites, portals, and applications where trust matters. The company name is listed in the certificate details, which builds extra trust with visitors.

Extended Validation (EV)

The Extended Validation certificate offers the highest validation level. In addition to all the OV certificate checks, an extensive verification of the organization is carried out, including checking the physical address and operational status. Issuance can take up to two weeks. EV certificates are intended for large companies, financial institutions, and government organizations that want to convey the highest level of trustworthiness.

Comparing validation levels

Feature	DV	OV	EV
Validation	Domain	Domain + organization	Extensive
Issuance time	Minutes	1-3 days	1-2 weeks
Price	Free - €50/year	€50-200/year	€150-500/year
Suitable for	Blogs, small sites	Business websites	Banks, government
Company name visible	No	In certificate	In certificate

Installing and Managing an SSL Certificate

Installation steps

Installing an SSL certificate starts with generating a Certificate Signing Request (CSR) on your server. This creates a private key that must remain secret. You send the CSR to the certificate authority, which issues the certificate after validation. Install the certificate together with any intermediate certificates on your web server. Test the installation with SSL Labs to check everything is configured correctly and you achieve a good security score.

Setting up automatic renewal

An expired SSL certificate is one of the most common causes of browser warnings that scare off visitors. Prevent this by setting up automatic renewal. Free certificates expire after 90 days and can be renewed automatically with tools such as Certbot. Commercial certificates usually have a one-year term. Set reminders well before the expiry date and test the renewal process before it's actually needed.

Want to know more about why SSL matters? Read our article about why an SSL certificate is needed for background information.

SSL Certificate: Frequently Asked Questions

Is a free SSL certificate just as safe as a paid one?

Yes, in terms of encryption strength, a free certificate from providers such as Let's Encrypt is just as safe as a paid certificate. The difference is in the validation level, the warranty, and the support. Free certificates offer only Domain Validation, while paid certificates also offer Organization and Extended Validation. Paid certificates also come with a financial guarantee if something goes wrong and direct support from the certificate authority.

How long is an SSL certificate valid?

Free Let's Encrypt certificates are valid for 90 days and are renewed automatically. Paid certificates usually have a one-year term. The trend is toward shorter validity periods for better security. Make sure you have automatic renewal set up or set a reminder well before the expiry date. An expired certificate shows a warning in the browser that scares off visitors.

Do I need an SSL certificate for a blog?

Yes, an SSL certificate is essential even for a blog. Google uses HTTPS as a ranking factor, so without SSL you rank lower in search results. Browsers show a warning for websites without SSL, which scares off visitors. If your blog has a contact form, comment option, or newsletter signup, personal data is being processed that needs protection. A free certificate is sufficient for most blogs.

Can I move an SSL certificate to a different server?

Yes, you can move an SSL certificate by exporting the certificate file and private key and importing them on the new server. With free certificates it's often easier to request a new certificate on the new server, which only takes a few minutes. With expensive EV certificates it's worth migrating the existing certificate to make use of the remaining validity period.

SSL Certificate: Practical Implementation Tips

Detecting and solving mixed content

After activating SSL you may encounter mixed content warnings. This means your page is loaded via HTTPS, but some resources such as images, scripts, or stylesheets are still requested via HTTP. Open the browser console to identify mixed content. Update the URLs in your database from http to https. Use a find-and-replace tool or plugin to do this in bulk. Set up a Content-Security-Policy header to automatically upgrade mixed content to HTTPS.

Setting up HTTP to HTTPS redirection

After installing your SSL certificate, you need to make sure all visitors are automatically redirected from HTTP to HTTPS. Configure a 301 redirect in your .htaccess file or server configuration. This ensures both visitors and search engines always reach the secure version of your website. Don't forget to also update your sitemap and robots.txt with HTTPS URLs. Check your Google Search Console settings and add the HTTPS variant of your website as a property.

SSL Certificate: Frequently Asked Questions

Sources and references

• Let's Encrypt — Gratis SSL-certificaten (letsencrypt.org)
• Cloudflare — Learning Center (cloudflare.com/learning)
• SSL Labs — SSL Server Test by Qualys (ssllabs.com)
• Autoriteit Persoonsgegevens — AVG-informatie (autoriteitpersoonsgegevens.nl)