SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
your-extension.com
SSL/TLS Certificate
SSL/TLS Certificate for your-extension.com
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- your-extension.com
- Valid from
- Sep 20, 2026
- Valid until
- Dec 19, 2026 (87 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 052FAB7BC42111BCA1405A98E43F93640E65
- SHA-256 fingerprint
- 5E:AA:AD:B2:C0:30:8B:F8:47:44:45:51:A8:49:54:56:DF:94:A0:57:3E:52:36:05:99:00:C5:E0:97:CD:87:6C
- Chain
- YR2 → Root YR → ISRG Root X1
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
We've observed 1 previous certificate for this host. This certificate has been served since Sep 22, 2026.
Never get surprised by your-extension.com's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch your-extension.com continuously, notifying you the moment anything moves across all three signals:
Uptime
We visit the site from multiple regions worldwide and email you within minutes if it goes down, with a per-region breakdown so a real outage stands out from a regional blip.
DNS changes
We watch NS, MX, CAA, DNSSEC, CNAME and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.
TLS certificate
We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.
Free for your first domain: uptime, DNS, and certificate together. No credit card.