SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
office365filesecurity.com
SSL/TLS Certificate
SSL/TLS Certificate for office365filesecurity.com
Untrusted chain- Issued by (CA)
- Microsoft Corporation
- Subject
- authyprodservices.com
- Valid from
- Apr 15, 2026
- Valid until
- Oct 12, 2026 (4 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 410011FD5A5A33B0C45DF19C9C00000011FD5A
- SHA-256 fingerprint
- EC:1C:E3:DE:D5:18:07:A5:E7:C6:D4:07:9E:85:1C:2A:00:AD:D5:A4:E7:43:85:D5:5B:A8:A8:2E:84:90:FF:6F
- Chain
- —
Certificate Authority Authorization (CAA)
CAA restricts issuance to microsoft.com; we couldn't map the serving CA (Microsoft Corporation) to one of these identifiers.
This certificate has been served since Aug 26, 2026.
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Uptime
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DNS changes
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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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