Domain & DNS

Check Your SSL Certificate

Verify HTTPS works, HTTP redirects to it, and the certificate chain is trusted.

Problem: Your website may show security warnings or have an expired or misconfigured certificate.

We connect to your domain over HTTPS, confirm the handshake succeeds against a trusted root, and check whether plain HTTP is redirected to the secure version.

Free. No account required.

What we'll check

  • HTTPS connection succeeds
  • Certificate chain is trusted
  • HTTP redirects to HTTPS
  • HSTS header present
  • Mixed-content signals in the HTML

What SSL/TLS actually does

TLS encrypts traffic between the visitor and your server and proves the server is who it claims to be. Without a valid certificate, browsers show a full-page interstitial warning that stops most visitors.

Common SSL errors and what causes them

  • NET::ERR_CERT_DATE_INVALID — the certificate expired. Renewal or auto-renewal failed.
  • NET::ERR_CERT_COMMON_NAME_INVALID — the certificate does not cover the hostname used, often www versus the apex domain.
  • NET::ERR_CERT_AUTHORITY_INVALID — self-signed certificate, or a missing intermediate in the chain.
  • Mixed content warnings — the page loads over HTTPS but pulls images or scripts over HTTP.

How to fix certificate problems

  • Reissue the certificate and confirm the automated renewal job runs.
  • Include every hostname you serve, including www.
  • Install the full chain, not just the leaf certificate.
  • Redirect all HTTP traffic to HTTPS with a 301.
  • Add Strict-Transport-Security once HTTPS is stable everywhere.
  • Update hard-coded http:// asset URLs in your database or templates.

Does SSL affect SEO?

HTTPS is a lightweight ranking signal, but the real impact is behavioural: a browser warning stops visitors before they see the page, and referral data from HTTPS sources is lost on HTTP pages.

Frequently asked questions

How often do SSL certificates expire?
Free automated certificates such as Let's Encrypt last 90 days and renew automatically. Paid certificates typically run for a year.
Do I need to pay for an SSL certificate?
For most business websites, no. A free automated certificate provides the same encryption. Paid certificates mainly add organisation validation and warranties.
What is HSTS?
A response header that tells browsers to only ever connect to your domain over HTTPS, preventing downgrade attacks. Enable it once HTTPS works on every subdomain you serve.

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