Learn about SSL certificate types, validity, common errors, and HTTPS security
Validation Level: Domain ownership only
Issuance Time: Auto-issued within minutes
Best For: Personal blogs, small websites
Price: Free (Let's Encrypt) and up
Features: Quick to obtain, basic encryption
Validation Level: Verifies company/organization authenticity
Issuance Time: 1-3 business days
Best For: Business websites, e-commerce, SaaS
Price: $70-$700/year
Features: Company name shown in certificate details
Validation Level: Strictest identity verification
Issuance Time: 3-7 business days
Best For: Finance, banking, large enterprises
Price: $700-$4200/year
Features: Company name in address bar (some browsers)
| Feature | DV | OV | EV |
|---|---|---|---|
| Domain Validation | ✅ | ✅ | ✅ |
| Organization Validation | ❌ | ✅ | ✅ |
| Strict Identity Check | ❌ | ❌ | ✅ |
| Company Name Display | ❌ | ✅ Certificate Details | ✅ Address Bar |
| Trust Level | Basic | Standard | Highest |
| Issuance Speed | Minutes | 1-3 days | 3-7 days |
Enter SSL certificate expiration date to calculate days remaining
The SSL certificate has expired, and the browser refuses to connect.
✅ Solution: Renew the SSL certificate and redeploy. Set up reminders 30 days before expiration.
The certificate was issued for a different domain than the one being accessed.
✅ Solution: Ensure the certificate covers all subdomains (use SAN/UCC certificates or wildcard certificates).
The certificate was issued by an unknown CA, or a self-signed certificate is being used.
✅ Solution: Use a trusted CA (such as Let's Encrypt, DigiCert, or Sectigo) to issue the certificate.
HTTP resources (images, scripts, etc.) are loaded on an HTTPS page.
✅ Solution: Change all resource links to HTTPS, or use protocol-relative URLs and upgrade-insecure-requests.
The client and server TLS versions are incompatible.
✅ Solution: Ensure the server supports TLS 1.2+, and disable SSLv3 and TLS 1.0/1.1.
Missing intermediate certificates, causing verification failure on some clients.
✅ Solution: Install the complete certificate chain on the server (server certificate + intermediate certificates).
| Feature | HTTP | HTTPS |
|---|---|---|
| Default Port | 80 | 443 |
| Encryption | None | TLS/SSL |
| Data Security | ❌ | ✅ |
| SEO Impact | No boost | Ranking improvement |
| HTTP/2 Support | Partial | Full support |
| Performance | Slightly faster (no encryption overhead) | TLS 1.3 has negligible overhead |