Valid SSL certificate
The SSL certificate is like the site's ID card. It proves the site is who it claims to be and that communication is encrypted. It has an exp…
Analyse my site for freeUnderstanding "Valid SSL certificate"
An SSL/TLS certificate is a digital file that serves two essential roles: it authenticates your server's identity (proving you own the domain) and it encrypts communications between the browser and server. It is issued by a Certificate Authority (CA) — a trusted third-party organisation like Let's Encrypt, DigiCert or Comodo — after verifying your rights over the domain.
Certificates have a limited lifespan. Let's Encrypt enforces 90 days. Commercial certificates typically last 1 or 2 years. An expired certificate immediately triggers a blocking warning in browsers, making your site practically inaccessible. Visitors see a large red error page that most do not get past.
(Let's Encrypt, DigiCert…)
domain.com · valid 90d
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How TheSiteFuse checks "Valid SSL certificate"
TheSiteFuse connects via TLS to the domain and extracts the presented certificate. The check verifies the expiry date, the validity of the certification chain (intermediate and root certificates must be recognised), and the match between the Common Name (CN) or Subject Alternative Names (SANs) and the audited domain. A valid certificate with an incomplete chain triggers errors on some browsers and Android devices.
Why "Valid SSL certificate" matters
An invalid or expired certificate has immediate and severe consequences:
- Browser blocking — Chrome, Firefox, Safari and Edge display a red error page "Your connection is not private" that blocks access. Most users leave immediately.
- Immediate SEO impact — Google can no longer crawl pages protected by an invalid certificate, causing ranking drops.
- Trust loss — once a user sees the security warning on your site, it is very hard to restore their confidence.
- Integration failures — third-party services (webhooks, APIs, mobile apps) calling your domain fail immediately with an invalid certificate.
Fix "Valid SSL certificate" step by step
Check the expiry date
openssl s_client -connect yoursite.com:443 -servername yoursite.com 2>/dev/null | openssl x509 -noout -dates
The notBefore and notAfter fields show the validity period.
Test automatic renewal
sudo certbot renew --dry-run sudo systemctl status certbot.timer
If the timer is missing, add a cron job:
sudo crontab -e # Add this line: 0 3 * * * certbot renew --quiet && systemctl reload apache2
Verify the certificate chain
An incomplete chain causes errors on Android and less common browsers. Test your site on SSL Labs (ssllabs.com/ssltest/) — it clearly indicates if the chain is complete and provides correction instructions.
Monitor expiry proactively
Set up email alerts 30 days before expiry. Monitoring services automatically send certificate expiry alerts — essential to avoid unexpected outages.
Reference resource
To deepen your understanding of the technical concepts behind this check, see the dedicated Wikipedia article.
Wikipedia — Valid SSL certificateDoes your site pass this check?
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