SSL Certificates Explained: What They Are and Why You Need One

What is an SSL Certificate?#

An SSL certificate (Secure Sockets Layer certificate, though it’s actually TLS now) is a digital certificate that enables HTTPS encryption on your website. It serves two main purposes:

1. Encrypts data between visitors’ browsers and your server
2. Verifies your website’s identity to visitors

Think of it like a passport for your website—it proves who you are and ensures secure communication.

The Visual Indicator#

When a website has a valid SSL certificate, you’ll see:

• Padlock icon in the browser’s address bar
• “https://” at the beginning of the URL (instead of “http://”)
• “Secure” indicator in some browsers
• Green bar (for Extended Validation certificates, though less common now)

When a website lacks SSL, browsers show:

• “Not Secure” warning in the address bar
• “http://” in the URL
• Warning messages when users try to enter information

In 2026, SSL/HTTPS isn’t optional—it’s essential.

SSL vs TLS: What’s the Difference?#

TLS (Transport Layer Security) is the modern name for what was originally called SSL (Secure Sockets Layer).

History#

• SSL 1.0: Never released publicly (security flaws)
• SSL 2.0: Released 1995, deprecated 2011
• SSL 3.0: Released 1996, deprecated 2015 (POODLE vulnerability)
• TLS 1.0: Released 1999, deprecated 2021
• TLS 1.1: Released 2006, deprecated 2021
• TLS 1.2: Released 2008, widely used
• TLS 1.3: Released 2018, recommended

Current status: We use TLS 1.2 and TLS 1.3, but people still commonly say “SSL” when referring to the technology. The terms are often used interchangeably, though technically we’re using TLS.

What People Mean#

When people say “SSL certificate” or “SSL/HTTPS,” they typically mean:

• The certificate that enables HTTPS encryption
• The encryption protocol (TLS)
• The overall secure connection technology

Both terms refer to the same thing—secure, encrypted connections.

How SSL/TLS Works#

The Encryption Process#

Here’s what happens when you visit an HTTPS website:

1. Browser requests HTTPS connection (visits https://example.com)
2. Server presents SSL certificate to browser
3. Browser verifies certificate (checks if it’s valid, trusted, matches domain)
4. Encrypted connection established if certificate is valid
5. Data is encrypted before transmission
6. Data is decrypted upon receipt
7. Secure communication continues

This happens automatically and invisibly to users—if it’s working, you just see the padlock.

What Gets Encrypted#

SSL/TLS encrypts all data between browser and server:

• Login credentials (usernames, passwords)
• Payment information (credit cards, bank details)
• Personal information (addresses, phone numbers, emails)
• Form submissions (contact forms, surveys)
• Session data (cookies, session IDs)
• All HTTP traffic (everything in the connection)

Without SSL, this data is sent in plain text—anyone intercepting the connection can read it.

The Handshake Process#

TLS Handshake (simplified):

1. Client Hello: Browser sends supported TLS versions and cipher suites
2. Server Hello: Server responds with chosen TLS version and cipher suite
3. Certificate Exchange: Server sends SSL certificate
4. Key Exchange: Browser and server establish encryption keys
5. Encryption Begins: Secure connection established

This handshake happens in milliseconds, establishing encrypted communication.

Why You Need SSL/HTTPS#

1. Security: Protect Your Visitors#

SSL encrypts data, preventing:

• Eavesdropping: Attackers can’t read intercepted data
• Man-in-the-middle attacks: Data can’t be modified in transit
• Session hijacking: Encrypted sessions are harder to steal
• Data theft: Sensitive information is protected

Without SSL, attackers can:

• Intercept login credentials
• Steal payment information
• Read form submissions
• Modify content in transit
• Hijack user sessions

SSL protects both you and your visitors.

2. Google’s “Not Secure” Warning#

Browsers mark HTTP sites as insecure:

• Chrome shows “Not Secure” in address bar
• Firefox shows warning icons
• Safari shows “Not Secure” warnings
• Users see security warnings

This hurts:

• User trust (visitors leave when seeing warnings)
• Conversions (people don’t enter information on insecure sites)
• Professional appearance (looks unprofessional)
• Credibility (appears outdated or careless)

3. SEO Ranking Factor#

Google confirmed HTTPS is a ranking signal:

• HTTPS sites rank better than HTTP
• Google prefers secure sites
• Mobile-first indexing considers security
• Security is part of page experience signals

While content quality matters more, HTTPS can provide a ranking boost, especially for competitive keywords.

4. Required for Modern Features#

Many web features require HTTPS:

• Service Workers: Enable Progressive Web Apps (PWAs)
• Geolocation API: Location services
• Push Notifications: Browser notifications
• Camera/Microphone: Media access
• Payment Request API: Native payment processing
• HTTP/2: Modern protocol (works over HTTPS)
• Browser features: Many modern APIs require secure context

Without HTTPS, you can’t use these modern web capabilities.

5. Payment Processing Requirements#

PCI DSS compliance requires HTTPS:

• If you accept credit cards, HTTPS is mandatory
• Payment processors require SSL
• PCI compliance audits check for HTTPS
• Encryption is required for card data

E-commerce sites must have SSL for legal and compliance reasons.

6. User Trust and Credibility#

SSL builds trust:

• Padlock icon shows security
• HTTPS signals professionalism
• Visitors feel safer entering information
• Builds brand credibility

Studies show visitors are more likely to:

• Make purchases on HTTPS sites
• Enter contact information
• Trust the website
• Return to the site

Types of SSL Certificates#

1. Domain Validation (DV) Certificates#

What they verify: Domain ownership only

Validation process:

• Prove you control the domain (via email, DNS, or file upload)
• Automated validation (minutes to hours)
• No business verification

Best for: Personal sites, blogs, small businesses

Cost: Usually free (Let’s Encrypt)

What visitors see: Padlock icon, HTTPS

2. Organization Validation (OV) Certificates#

What they verify: Domain ownership + business registration

Validation process:

• Domain ownership verification
• Business registration check
• Manual review (1-3 days)
• Company information in certificate

Best for: Business websites wanting more verification

Cost: $50-200/year

What visitors see: Padlock icon, HTTPS, organization name in certificate details

3. Extended Validation (EV) Certificates#

What they verify: Domain ownership + extensive business verification

Validation process:

• Domain ownership verification
• Extensive business verification
• Legal entity verification
• Manual review (5-10 days)
• Organization name in address bar (historically, less common now)

Best for: Large organizations, financial institutions

Cost: $200-1000+/year

What visitors see: Padlock icon, HTTPS, organization name in certificate

Note: EV certificates historically showed organization name in address bar, but modern browsers have moved away from this. The value difference between OV and EV is minimal now.

Which Certificate Do You Need?#

For most websites: DV certificate (free from Let’s Encrypt)

Why DV is sufficient:

• Provides same encryption as OV/EV
• Same security level
• Free and easy to obtain
• Works perfectly for most sites

Consider OV/EV if:

• You want organization name in certificate
• Industry regulations require it
• You want additional verification display

Reality: DV certificates from Let’s Encrypt work perfectly for 99% of websites. The encryption is the same regardless of certificate type.

Free SSL Certificates: Let’s Encrypt#

Let’s Encrypt is a free, automated Certificate Authority that provides SSL certificates to anyone.

What is Let’s Encrypt?#

• Non-profit organization
• Free SSL certificates for everyone
• Automated issuance and renewal
• Supported by major browsers
• Trusted by all major browsers

Benefits of Let’s Encrypt#

Free: No cost for SSL certificates

Automated: Automatic issuance and renewal

Easy: Many hosts offer one-click installation

Secure: Same encryption as paid certificates

Trusted: Supported by all major browsers

Open: Non-profit, transparent, community-driven

How to Get Let’s Encrypt SSL#

Option 1: Hosting Provider (Easiest)

• Most hosts offer free Let’s Encrypt SSL
• One-click installation in hosting panel
• Automatic renewal handled by host
• No technical knowledge required

Option 2: Manual Installation

• Install Certbot (Let’s Encrypt client)
• Run commands to generate certificate
• Configure web server
• Set up automatic renewal

Option 3: cPanel/Control Panel

• Many control panels have Let’s Encrypt integration
• Click to install SSL
• Automatic renewal

Best option: Use your hosting provider’s one-click SSL installation—it’s easiest and handles renewal automatically.

SSL Certificate Installation#

How Installation Works#

The process varies by host, but typically:

1. Request certificate (via hosting panel or command line)
2. Domain verification (automated for Let’s Encrypt)
3. Certificate generated (within minutes)
4. Certificate installed on server
5. HTTPS enabled (automatic or manual redirect)
6. Renewal configured (automatic for Let’s Encrypt)

Common Hosting Providers#

Most hosts offer free SSL:

• Cloudflare: Free SSL for all plans
• Let’s Encrypt: Free, available via most hosts
• cPanel: Built-in Let’s Encrypt integration
• WordPress hosting: Usually includes free SSL
• Shared hosting: Most include free SSL now

Check your host’s documentation for SSL installation instructions specific to their platform.

After Installation#

What to do:

• ✅ Test HTTPS works (visit https://yoursite.com)
• ✅ Set up HTTP to HTTPS redirect (important!)
• ✅ Update internal links to HTTPS
• ✅ Update external links if possible
• ✅ Submit updated sitemap to Google Search Console
• ✅ Test site functionality (forms, checkout, etc.)

HTTP to HTTPS redirect is crucial—it ensures all traffic uses HTTPS, even if someone types HTTP.

SSL Certificate Renewal#

Automatic Renewal (Recommended)#

Let’s Encrypt certificates expire every 90 days, but automatic renewal is standard:

• Hosting providers handle renewal automatically
• Certbot can auto-renew certificates
• cPanel handles renewal automatically
• No manual intervention needed

Why 90 days? Security best practice—shorter validity periods limit damage if certificates are compromised.

Reality: With automatic renewal, you don’t need to worry about expiration.

Manual Renewal#

If automatic renewal isn’t working:

• Renew via hosting panel
• Run Certbot renewal command
• Contact host support for assistance

Signs renewal is needed:

• Certificate expiring soon
• Browser warnings about expired certificate
• HTTPS not working

Check certificate expiration:

• Click padlock in browser
• View certificate details
• Check expiration date
• Most tools show days until expiration

SSL Certificate Errors and Issues#

Common Errors#

1. “Your connection is not private”

• Cause: Invalid or expired certificate
• Solution: Check certificate validity, renew if needed
• For visitors: Don’t proceed if you see this (legitimate warning)

2. “NET::ERR_CERT_AUTHORITY_INVALID”

• Cause: Certificate not trusted by browser
• Solution: Ensure certificate is from trusted CA
• Check: Certificate chain is complete

3. “NET::ERR_CERT_COMMON_NAME_INVALID”

• Cause: Certificate doesn’t match domain name
• Solution: Ensure certificate is for correct domain
• Check: www vs non-www, subdomain issues

4. Mixed Content Warnings

• Cause: HTTP resources on HTTPS page (images, scripts, CSS)
• Solution: Update all resources to HTTPS
• Check: Browser console shows mixed content errors

Troubleshooting Steps#

1. Check certificate validity (click padlock, view certificate)
2. Verify domain matches certificate
3. Check expiration date (shouldn’t be expired)
4. Test on different browsers (isolate browser issues)
5. Check SSL labs (ssllabs.com/ssltest) for detailed analysis
6. Contact host support if issues persist

SSL and Website Performance#

Performance Impact#

SSL adds minimal overhead:

• Initial handshake: ~100-200ms (one-time per connection)
• Encryption/decryption: Negligible on modern hardware
• Overall impact: less than 1% on page load time
• Benefits outweigh costs: Performance impact is minimal

Modern TLS 1.3 is even faster:

• Faster handshake (0-RTT for returning visitors)
• Better performance than TLS 1.2
• Recommended for new implementations

HTTP/2 Benefits#

HTTP/2 requires HTTPS:

• Faster page loading (multiplexing, server push)
• Better performance than HTTP/1.1
• Requires HTTPS connection
• Another reason to use SSL

Bottom line: SSL’s security benefits far outweigh the minimal performance cost. Modern implementations are fast.

SSL Best Practices#

1. Use Strong TLS Versions#

Current recommendations:

• TLS 1.2: Widely supported, secure
• TLS 1.3: Recommended, fastest, most secure
• Disable TLS 1.0 and 1.1: Deprecated, insecure
• Disable SSL 3.0: Deprecated, vulnerable

Check your server configuration and ensure you’re using TLS 1.2 or 1.3.

2. Redirect HTTP to HTTPS#

Always redirect HTTP to HTTPS:

• Ensures all traffic uses encryption
• Prevents duplicate content issues
• Improves security
• Required for proper HTTPS implementation

Implementation:

# Apache
RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

# Nginx
server {
    listen 80;
    server_name example.com;
    return 301 https://$server_name$request_uri;
}

3. Update All Links to HTTPS#

Update internal links:

• Change http:// to https:// in content
• Update hardcoded links
• Use relative URLs where possible (//example.com)
• Check database for HTTP links

Use HTTPS everywhere:

• Images
• CSS files
• JavaScript files
• External resources
• API calls

4. Enable HSTS (HTTP Strict Transport Security)#

HSTS forces HTTPS connections:

• Browsers remember to use HTTPS
• Prevents downgrade attacks
• Improves security
• Reduces redirect overhead

Implementation:

Strict-Transport-Security: max-age=31536000; includeSubDomains

Important: Only enable HSTS after confirming HTTPS works perfectly—HSTS can cause issues if HTTPS breaks.

5. Monitor Certificate Expiration#

Set up monitoring:

• Automatic renewal (should handle this)
• Monitor expiration dates
• Set reminders (if needed)
• Test renewal process

Most hosts handle this automatically, but verify renewal is working.

Conclusion: SSL is Essential#

SSL/HTTPS is not optional in 2026—it’s essential:

Why you need it:

• ✅ Security: Protects visitor data
• ✅ SEO: Google ranking factor
• ✅ User trust: Builds credibility
• ✅ Browser requirements: Many features need HTTPS
• ✅ Modern standards: Expected by users and browsers

How to get it:

• ✅ Free SSL certificates available (Let’s Encrypt)
• ✅ Most hosts offer one-click installation
• ✅ Automatic renewal handles maintenance
• ✅ No technical expertise required (with hosting provider)

What to do:

• ✅ Get SSL certificate (free from your host)
• ✅ Install and enable HTTPS
• ✅ Redirect HTTP to HTTPS
• ✅ Update links to HTTPS
• ✅ Monitor and maintain

The bottom line: Every website needs SSL/HTTPS. It’s free, easy to install, and essential for security, SEO, and user trust. There’s no excuse not to have it.

If your site doesn’t have SSL, get it today. It’s one of the easiest and most important things you can do to improve your website.

For more on website security, check out our guide on website security basics and web hosting.