SSL Certificate Checker
Verify SSL certificate validity, expiry date, issuer, and TLS version.
What Is an SSL Certificate?
An SSL/TLS certificate authenticates a website's identity and enables encrypted HTTPS connections. Expired or invalid certificates trigger browser security warnings and can hurt SEO rankings.
What to Check
Common Use Cases
- Expiry monitoring — catch certificates approaching expiration before they cause browser warnings or outages.
- Chain validation — confirm intermediate certificates are properly configured, since missing links cause errors on some browsers/devices even when the cert appears valid on others.
- Post-renewal verification — confirm a newly renewed or reissued certificate deployed correctly after an update.
- Third-party/vendor checks — verify the SSL configuration of an API or service you integrate with before troubleshooting connection failures.
Example
A certificate expiring in 12 days with a valid chain and strong TLS 1.3 support is healthy today but needs renewal scheduled now — most outages from expired certs are avoidable with a 30-day expiry alert.
Frequently Asked Questions
What happens when an SSL certificate expires?
Browsers will show a security warning and typically block users from proceeding, effectively taking your site offline for most visitors until it's renewed.
What is a certificate chain issue?
It means the server isn't sending the full chain of intermediate certificates needed for browsers to verify trust up to a recognized root authority — a very common misconfiguration.
Is a self-signed certificate a problem?
For public-facing production sites, yes — browsers won't trust it and will show warnings. Self-signed certs are fine for internal/development use only.
How often should I renew my SSL certificate?
Most modern certificates (like Let's Encrypt) are valid for 90 days and are usually configured to auto-renew. Manually issued certificates can be valid for up to a year or more.