SSL Certificate Check: Validity, Chain, Protocols
The certificate is responsible for https: without it, the browser marks the site as unsafe, and some visitors leave before it loads. You can check the validity, chain, and supported protocols by checking the SSL certificate.
What to Look for in the Report
| Parameter | What Should Be |
|---|---|
| Validity | More than two weeks in advance; free certificates last about three months and renew automatically |
| Name in the Certificate | Matches the domain, including the www variant |
| Chain of Trust | Complete: without the intermediate certificate, some clients will show an error |
| Protocols | TLS 1.2 and 1.3; outdated versions are better disabled |
| Issuer | Well-known certification authority, not a self-signed certificate |
What to Do in Case of Errors
- Expired. Renew the certificate and check that auto-renewal is indeed working.
- Name Mismatch. Add the necessary domains to the certificate or set up a separate one.
- Incomplete Chain. Upload the intermediate certificate to the server.
- Mixed Content. Replace links to images, styles, and scripts from http to https, otherwise the browser will complain even with a valid certificate.
Free or Paid Certificate
For the purpose of checking validity, there is no difference: both the browser and the bot check validity, not price. Free certificates are issued automatically and renew themselves — this is sufficient for the overwhelming majority of sites. Paid certificates make sense where extended organization verification, insurance, or support for rare scenarios is needed. The main thing is that auto-renewal actually works: an expired expensive certificate is worse than a timely renewed free one.
How This Relates to Promotion
Https is a basic requirement: a site without it loses trust and visitors. Additionally, a certificate error hinders our checks: the page may become inaccessible for crawling. A complete picture of security is provided by Shield, and security headers are discussed in the article on security headers.