Check any domain
Try:
✓ Uses crt.sh — the official Certificate Transparency log database. No third-party proxies. All publicly trusted certificates are recorded there.
What is an SSL certificate checker?
An SSL certificate checker queries a domain to retrieve information about its TLS/SSL certificate — including whether it is currently valid, when it expires, and who issued it. This is essential for monitoring certificate health and preventing unexpected expiry.
An expired SSL certificate causes browsers to display security warnings to all visitors and can damage search rankings. Most certificates expire after 13 months — renew at least 30 days before expiry.
Frequently asked questions
What does an SSL checker do?
It retrieves the SSL certificate for a domain and shows the expiry date, issuer, common name and validity status — helping you verify your certificate is installed correctly.
How often do SSL certificates expire?
Since 2020, SSL certificates are issued for a maximum of 398 days. They must be renewed before expiry to avoid browser warnings and downtime.
What happens when an SSL certificate expires?
Browsers show a full-page security warning blocking visitor access. Search engines may penalise or delist the site. Set calendar reminders 60 and 30 days before expiry.
What is Let's Encrypt?
Let's Encrypt is a free Certificate Authority used by over 300 million websites. Ghost, Cloudflare and most hosting providers integrate with it automatically.
What's checked
Certificate validity status
Expiry date and days remaining
Certificate issuer / CA
Subject and common name
Total certs in CT logs
Best practices
Renew at least 30 days before expiry
Enable auto-renewal on your host
Use Let's Encrypt for free certs
Set calendar expiry reminders
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