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SSL Certificate Checker

Verify SSL certificate validity, expiry date, and certificate chain.

What is SSL Certificate Checker?

An SSL certificate secures the connection between your visitors and your website by encrypting all data in transit. Search engines like Google use HTTPS as a ranking factor, and browsers display warnings for sites without valid SSL certificates. Regular SSL monitoring prevents unexpected certificate expirations that can take your site offline.

How to use this tool

  1. Enter the domain name you want to check
  2. Our tool connects to the server on port 443
  3. View certificate details including issuer, validity dates, and remaining days
  4. Check the Subject Alternative Names (SAN) for covered domains

Frequently asked questions

How do I know if my SSL certificate is valid?
A valid SSL certificate must be issued by a trusted Certificate Authority (CA), not be expired, and cover the domain name you are checking. Our tool verifies all of these conditions and shows you exactly when your certificate expires.
What happens when an SSL certificate expires?
When an SSL certificate expires, browsers display a full-page security warning to visitors, effectively making your site inaccessible. Most visitors will leave immediately. Search engines may also temporarily drop your rankings. Always renew certificates before they expire.
Can I use a free SSL certificate?
Yes. Let's Encrypt provides free, automated SSL certificates that are trusted by all major browsers. Many hosting providers, including host4.ai, automatically provision and renew Let's Encrypt certificates for your domains.

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