SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
SSL/TLS Certificate for alr.cat
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- alr.cat
- Valid from
- Jul 28, 2026
- Valid until
- Oct 26, 2026 (77 days remaining)
- Public key
- EC 256-bit
- Serial
- 0507CE919A8F74AA8E15188BF69732E8F53B
- SHA-256 fingerprint
- A0:D3:D4:56:86:14:F1:F2:3D:11:BC:09:A7:58:64:DF:27:9F:2E:9A:72:ED:09:75:19:D3:F6:3F:E2:EF:15:9C
- Chain
- YE1 → 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 Jul 26, 2026.
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This is today's certificate. Turn on monitoring and we'll watch alr.cat continuously, notifying you the moment anything moves across all three signals:
Uptime
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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.
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