What is an SSL certificate and why do you need it?

What is an SSL certificate and how does it work?

SSL (Secure Sockets Layer) certificate is a digital security credential issued by a trusted organization known as a certificate authority (CA). Its main purpose is to verify the identity of a website owner and enable secure, encrypted communication between the server and the visitor’s browser. While the more modern TLS (Transport Layer Security) protocol is used today behind the scenes, the term “SSL certificate” is still commonly used.

Once an SSL certificate is installed, it creates a secure connection that prevents third parties from intercepting or altering transmitted data. This means all information – from personal details to payment data – is encrypted during transfer and can only be accessed by the sender and the intended recipient.

Without an SSL certificate, data is sent in plain, unencrypted form. This can be compared to sending a postcard: anyone who intercepts it can easily read its contents. With an SSL certificate, the transfer is more like sending a sealed and locked letter that only the recipient can open – significantly increasing security and visitor trust.

How to recognize an SSL connection?

• A padlock icon appears in the browser’s address bar
• The website address starts with https:// (the letter s stands for "secure")
• In some browsers, the company name may also be shown next to the address (for so-called EV certificates)

How does SSL work?

1. Visiting the site: The user enters the website address in the browser (e.g., https://mycompany.com)
2. Certificate presentation: The server sends its SSL certificate to the browser, containing the public key, owner information, issuer’s signature, and validity period
3. Authentication check: The browser verifies whether the certificate was issued by a trusted CA, is valid, and matches the domain
4. Encryption agreement: The browser and server generate and exchange a session key used to encrypt all further communication
5. Secure communication: Any data exchange (passwords, personal and payment information) is encrypted and can only be read by the recipient with the correct key

Why use SSL?

• Encryption: Prevents third parties from intercepting and reading transmitted data
• Authentication: Confirms you are connecting to the genuine website, not a fake copy
• Data integrity: Ensures that data is not altered during transmission

In practice, this means a customer can safely enter credit card details in an online store, forms containing personal data remain protected from malicious actors, and browsers mark the site as secure – which also has a positive effect on search engine rankings.

SSL certificates are no longer reserved for banks and large e-commerce sites – they are recommended for every website. Even if your site only collects basic information through a contact form, an SSL certificate ensures secure data transfer while also boosting visitor confidence in your brand.

Main benefits of using an SSL certificate for your website

An SSL certificate is not just a technical upgrade – it is a key element for the security, trust, and visibility of your website. By using it, you gain:

• User data protection: All transferred data (passwords, email addresses, payment details) is encrypted to prevent interception or theft
• Greater visitor trust: The padlock icon and HTTPS label in the address bar signal that your site takes security seriously
• Better search rankings: Google and other search engines prioritize sites with HTTPS
• Protection against phishing attacks: Makes it harder for malicious sites to mimic your domain and mislead users
• Prevention of browser warnings: Sites without SSL are often marked as “Not secure,” which can reduce traffic and trust

Impact on speed

Minimal. Modern servers and browsers use optimized protocols (HTTP/2, TLS 1.3) that make the impact on loading speed almost unnoticeable. In fact, switching to HTTPS with HTTP/2 can even make a website load faster.

Impact on SEO and business results

• Advantage in Google’s algorithm: HTTPS is a ranking signal, increasing the chance to outrank competitors
• Higher CTR: Users are more likely to click on results marked as secure
• Brand reputation boost: Consistent use of SSL improves long-term recognition and readiness for future security requirements

What types of SSL certificates exist and which one is right for you?

SSL certificates differ in terms of the level of protection and the way ownership is verified. The right choice depends on the type of website, the amount of data you process, and the level of trust you want to build with visitors.

Types by validation level

• DV (Domain validation): Only domain ownership is verified. The fastest and most affordable option, suitable for blogs, personal websites, and basic company presentation sites.
• OV (Organization validation): In addition to the domain, the company’s identity is also verified. Suitable for business websites where user trust is important.
• EV (Extended validation): The highest level of verification, displaying the company’s legal name in the browser. Recommended for e-commerce and financial services.

Types by scope of protection

• Single-domain: Protects one domain (e.g., mycompany.com).
• Wildcard: Protects the domain and all its subdomains (e.g., *.mycompany.com) – ideal for larger web projects.
• Multi-domain (SAN): Protects multiple different domains with a single certificate – useful for companies with several brands.

How to choose the right SSL certificate?

• For basic websites: A DV certificate is quick and cost-effective.
• For business websites: An OV certificate strengthens the company’s credibility.
• For online stores and financial sites: An EV certificate provides the highest trust level and the best protection.
• For multiple subdomains: A Wildcard or Multi-domain certificate reduces costs and simplifies management.

How much does an SSL certificate cost and are there free options?

The price of an SSL certificate depends on its type, level of validation, and scope of protection. Both free and paid options are available, with the choice affecting the level of trust and additional features.

Paid options

• DV (Domain validation): From €5 to €30 per year – suitable for basic websites and blogs.
• OV (Organization validation): From €20 to €150 per year – suitable for business sites where company credibility is important.
• EV (Extended validation): From €40 to €600 per year – the highest trust level, recommended for e-commerce and financial services.
• Wildcard and multi-domain: From €40 to €300 per year – for protecting multiple subdomains or domains with a single certificate.

Factors affecting the price

• Level of validation (DV, OV, EV)
• Scope of protection (single domain, multiple domains, subdomains)
• Validity period (1–2 years)
• Reputation and support of the provider

Free options

• Let’s Encrypt: Free DV certificate valid for 90 days, with an option for automatic renewal.
• Cloudflare SSL: Free certificate through CDN service – suitable for sites using Cloudflare.
• ZeroSSL: Free DV certificates with basic support and an option to upgrade.

Free options are great for personal projects and smaller websites, but larger companies often choose paid certificates due to additional security features, warranties, and higher levels of user trust.

SSL certificate installation process – step by step

Installing an SSL certificate can be simple or slightly more complex, depending on your hosting provider, the type of certificate, and your technical knowledge. Below is the standard process that applies to most websites.

1. Choosing the right certificate

• Determine whether you need a DV, OV, EV, Wildcard, or Multi-domain certificate.
• Select a reliable provider (e.g., Let’s Encrypt, Namecheap, GlobalSign, SSL.com).

2. Generating a CSR (Certificate Signing Request)

• The CSR is generated on the server where your website is hosted.
• It contains information about the domain and the company (for OV and EV certificates).
• A private key is created along with the CSR, which must be stored securely.

3. Verifying domain ownership

• For DV certificates, this is done via email, a DNS record, or a file placed on the server.
• OV and EV certificates require additional company identity verification (e.g., official documents, phone verification).

4. Issuing the certificate

• After successful verification, the provider issues the SSL certificate in file formats such as .crt, .pem, or .p7b.
• The certificate is usually valid for 90 days (free) to 1–2 years (paid).

5. Installing the certificate on the server

• In your hosting control panel (e.g., cPanel, Plesk), find the SSL/TLS section.
• Upload the certificate, the intermediate certificate (CA bundle), and the private key.
• Save the changes and enable HTTPS.

6. Redirecting HTTP to HTTPS

• Add a redirect rule in the .htaccess file or via server settings.
• Ensure all links (images, CSS, scripts) use HTTPS to avoid mixed content errors.

7. Testing

• Use tools such as SSL Labs Test, Why No Padlock, or SSL Checker to verify proper installation.
• Check the site’s functionality across different browsers and devices.

8. Renewing the certificate

• Free certificates (e.g., Let’s Encrypt) must be renewed every 90 days – set up automatic renewal.
• Renew paid certificates before they expire to avoid “Not secure” warnings.

If you use managed hosting, most of these steps are handled by the hosting provider. You simply choose the certificate and enable HTTPS in the control panel.

Common SSL mistakes and how to avoid them

While installing an SSL certificate is relatively straightforward, certain mistakes can reduce its effectiveness or cause the site to be marked as insecure despite having a certificate.

• Mixed content: Some images, scripts, or other files are still loaded over http:// instead of https://, triggering browser warnings and lowering visitor trust.
• Expired certificate: SSL certificates have an expiration date and must be renewed on time, or the site will appear unsafe.
• Missing HTTPS redirects: If part of the site is still accessible over HTTP, users may unknowingly use an unsecured connection.

To avoid these issues, regularly check your certificate, set up automatic renewal (if possible), and ensure all links and resources on the site load over a secure protocol.

Additional note: SSL encrypts data between the browser and the server, preventing interception. However, it does not protect against attacks such as SQL injection, XSS, or malware. For complete security, other measures are necessary, such as a firewall, regular updates, and backups.

Why you can’t go without an SSL certificate today

In today’s digital world, where vast amounts of data are exchanged daily, the SSL certificate has become a basic security standard. It is no longer just about protecting sensitive information but also about building trust, improving user experience, and maintaining a good position in search engine results.

Without an SSL certificate, you risk:

• Browser warnings that your site is not secure
• Loss of visitor and customer trust
• Lower search engine rankings
• Theft or misuse of user data

Do I need SSL even if I don’t collect personal data? Yes. Search engines and browsers now prioritize websites with an HTTPS connection, regardless of whether they collect personal information or not. SSL increases user trust, protects the integrity of data during transfer, and prevents third parties from tampering with site content.

Whether it’s a personal blog, a company presentation site, or a large e-commerce store, installing an SSL certificate is now essential. Without it, your website simply cannot meet modern security standards and user expectations.