SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
obsidian-os.app
SSL/TLS Certificate
SSL/TLS Certificate for obsidian-os.app
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- obsidian-os.app
- Valid from
- Oct 4, 2026
- Valid until
- Jan 2, 2027 (85 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 06236805DBCD6BC4A0151F4DF16F08647AF0
- SHA-256 fingerprint
- 85:AC:2D:1C:1C:36:69:D6:A5:A1:D1:B6:27:34:F4:47:D5:49:82:82:30:EC:BA:A8:D9:66:67:BE:38:40:75:C9
- 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.
Never get surprised by obsidian-os.app's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch obsidian-os.app 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.
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