Free tool
SSL certificate and TLS checker
An expired or untrusted certificate shows visitors a full-page browser warning, which is often worse for a small business than a quiet outage. This checker connects to your site the way a browser would and reports the certificate and protocol it sees.
What this checks
- Certificate trusted by the system trust store
- Whether the certificate covers your website name (subject alternative names)
- Days until expiry (warns inside 30 days; severity rises at 14 and 7 days)
- Issuer, subject, valid-from and valid-to dates
- Negotiated TLS protocol version (flags TLS 1.0/1.1)
- Whether the site loads over HTTPS and how fast it responds
How to use it
- Enter your domain.
- Read the certificate details: issuer, days left and the names it covers.
- If expiry is near, check that auto-renewal is enabled at your host or certificate provider.
- If the certificate is untrusted or for a different name, make sure the full chain is installed and the hostname matches.
Methodology and limitations
Only the protocol negotiated with this client is observed; PixelPrivate does not enumerate every supported cipher or protocol. PixelPrivate performs passive checks against publicly visible configuration only. It does not test for exploitable vulnerabilities, so a clean result is not a guarantee of security. Read the full security methodology.
Key terms
Frequently asked questions
Are free certificates less secure?
No. Free certificates from Let’s Encrypt provide the same encryption. They are shorter-lived, so automatic renewal matters.
Why does my certificate work in a browser but fail here?
Usually an incomplete certificate chain: browsers can sometimes fetch missing intermediates, other clients cannot.
Keep this check running automatically
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