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THE CERTIFICATE BEHIND THE CONNECTION

TLS certificate checker.

Inspect SSL/TLS certificates for any public domain or subdomain.

Checks HTTPS on port 443, including subject alternative names, validity dates and the presented chain.

SSL certificate

TLSv1.2

fmt32.net · 217.160.178.78:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. SSL operation failed with code 1. OpenSSL Error messages: error:0A000086:SSL routines::certificate verify failed
The certificate has expired.

Certificate verification failed

Subject
CN=serve-u.de
Issuer
C=US O=Let's Encrypt CN=Let's Encrypt Authority X3
Valid from
2019-08-09T04:30:35+00:00
Expires
2019-11-07T04:30:35+00:00
Days remaining
-2529
Serial (hex)
0330025093DDC1B1F0729312F67159F7EBEB
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:serve-u.de, DNS:serveu.de, DNS:webmail.serve-u.de, DNS:www.serveu.de

SHA-256 fingerprint

DE:F4:71:41:B3:70:50:64:E2:A0:6C:CD:D1:FC:F2:DA:8E:DB:6C:C8:78:E8:B9:D5:6E:01:EB:30:7E:F9:CE:F9
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
62:A1:F3:A0:ED:65:58:2D:76:15:DC:06:3A:94:2E:DE:7C:D1:5D:E6
authorityKeyIdentifier
A8:4A:6A:63:04:7D:DD:BA:E6:D1:39:B7:A6:45:65:EF:F3:A8:EC:A1
authorityInfoAccess
OCSP - URI:http://ocsp.int-x3.letsencrypt.org CA Issuers - URI:http://cert.int-x3.letsencrypt.org/
subjectAltName
DNS:serve-u.de, DNS:serveu.de, DNS:webmail.serve-u.de, DNS:www.serveu.de
certificatePolicies
Policy: 2.23.140.1.2.1 Policy: 1.3.6.1.4.1.44947.1.1.1 CPS: http://cps.letsencrypt.org
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : E2:69:4B:AE:26:E8:E9:40:09:E8:86:1B:B6:3B:83:D4: 3E:E7:FE:74:88:FB:A4:8F:28:93:01:9D:DD:F1:DB:FE Timestamp : Aug 9 05:30:35.381 2019 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:F3:43:04:E0:CD:75:B1:7E:F9:C4:B6: 0D:F4:16:2F:30:09:2E:0E:85:70:2D:1A:9D:45:70:FA: 9E:82:89:13:BC:02:21:00:88:8B:FF:AA:E9:E9:C9:0C: 59:EF:00:07:D2:F4:74:35:77:F3:D0:DD:61:3D:6F:F8: 2F:4A:EC:F0:2F:17:FA:3D Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 29:3C:51:96:54:C8:39:65:BA:AA:50:FC:58:07:D4:B7: 6F:BF:58:7A:29:72:DC:A4:C3:0C:F4:E5:45:47:F4:78 Timestamp : Aug 9 05:30:35.912 2019 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:48:C4:51:9B:FD:FB:79:57:0C:6E:A3:E1: 1F:85:7D:4F:3B:50:99:05:02:9B:0A:4F:D5:DF:BC:E1: E2:83:93:38:02:21:00:A1:B7:F6:8B:93:15:98:89:E4: C3:65:A4:AF:88:D8:55:08:71:6A:F8:8D:92:9B:2B:CC: 15:6F:AC:AA:67:2E:13
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: ECDHE-RSA-AES128-GCM-SHA256 · Checked 2026-10-09T17:27:31+00:00

Server-presented chain · 1 additional certificate

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=Let's Encrypt Authority X3
Issuer
O=Digital Signature Trust Co. CN=DST Root CA X3
Valid from
2016-03-17T16:40:46+00:00
Expires
2021-03-17T16:40:46+00:00
Days remaining
-2033
Serial (hex)
0A0141420000015385736A0B85ECA708
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

25:84:7D:66:8E:B4:F0:4F:DD:40:B1:2B:6B:07:40:C5:67:DA:7D:02:43:08:EB:6C:2C:96:FE:41:D9:DE:21:8D
Certificate extensions & PEM
basicConstraints
CA:TRUE, pathlen:0
keyUsage
Digital Signature, Certificate Sign, CRL Sign
authorityInfoAccess
OCSP - URI:http://isrg.trustid.ocsp.identrust.com CA Issuers - URI:http://apps.identrust.com/roots/dstrootcax3.p7c
authorityKeyIdentifier
C4:A7:B1:A4:7B:2C:71:FA:DB:E1:4B:90:75:FF:C4:15:60:85:89:10
certificatePolicies
Policy: 2.23.140.1.2.1 Policy: 1.3.6.1.4.1.44947.1.1.1 CPS: http://cps.root-x1.letsencrypt.org
crlDistributionPoints
Full Name: URI:http://crl.identrust.com/DSTROOTCAX3CRL.crl
subjectKeyIdentifier
A8:4A:6A:63:04:7D:DD:BA:E6:D1:39:B7:A6:45:65:EF:F3:A8:EC:A1
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

One endpoint on port 443. Server-presented chain; no revocation, OCSP, CT or full TLS security scan.

View certificate JSON

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