SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
my-external-domain.com
SSL/TLS Certificate
SSL/TLS Certificate for my-external-domain.com
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- my-external-domain.com
- Valid from
- Sep 21, 2026
- Valid until
- Dec 20, 2026 (76 days remaining)
- Public key
- EC 256-bit
- Serial
- 0681416B820E5BFAC1927E18C7093ABBBE90
- SHA-256 fingerprint
- 02:A6:7B:35:BE:0C:9E:19:E2:05:D3:E0:24:51:E3:7D:D7:8F:AB:4C:8F:E7:78:DA:BA:F6:B3:CA:A1:64:F1:88
- Chain
- YE2 → Root YE → ISRG Root X2 → ISRG Root X1
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
This certificate has been served since Sep 30, 2026.
Never get surprised by my-external-domain.com's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch my-external-domain.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.