SSL Certificate Checker - Verify HTTPS Certs Online
SSL Certificate Checker
Inspect Any Domain's HTTPS Certificate
Ready to Check
Enter a domain above to inspect its SSL certificate.
Understanding SSL/TLS Certificates
Expiry Monitoring
An expired certificate breaks HTTPS entirely for visitors — check expiry dates before they catch you by surprise.
Issuer Verification
Confirm a certificate was issued by the certificate authority you expect (e.g. Let's Encrypt, DigiCert).
Domain Coverage
Check the Subject Alternative Names list to see every domain and subdomain a certificate actually covers.
Real TLS Handshake
Performs an actual TLS connection server-side to read the live certificate, not a cached or third-party API result.
Why Certificates Expire
Modern SSL/TLS certificates deliberately have short lifespans (often 90 days for Let's Encrypt) to limit the damage window if a private key is ever compromised. This makes automated renewal essential — a certificate that isn't renewed in time will show visitors a hard browser security warning, not a soft degradation.
Key Takeaways
- Live Handshake: Connects directly to port 443 and reads the certificate presented in real time.
- Expiry Countdown: See exactly how many days remain before a certificate needs renewal.
- SSRF-Protected: Connections are only permitted to hosts that resolve to a public IP address.