DNS
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

TLSv1.3

post.knipp.de · 195.253.54.4:443

Verified

Certificate chain, hostname and dates verified using this server’s CA store.

Subject
CN=post.knipp.de
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-09-18T18:49:19+00:00
Expires
2026-12-17T18:49:18+00:00
Days remaining
85
Serial (hex)
0612B43FB638ADC93C395130F0D62B90E90A
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:autoconfig.lebenohnedich.de, DNS:autodiscover.lebenohnedich.de, DNS:autodiscover.testmail.knipp.de, DNS:post.knipp.de

SHA-256 fingerprint

D7:86:BB:2D:0A:BF:B9:B7:E3:61:BF:A3:ED:46:90:87:47:2D:8D:E9:6F:16:E1:42:72:64:70:70:FC:42:0A:21
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
CA:50:E6:D3:24:20:2A:F9:23:E2:35:25:C2:81:9F:68:87:13:A5:42
authorityKeyIdentifier
1F:2F:35:BE:46:14:82:CD:40:B1:AE:79:2C:55:78:FA:F7:D4:68:FB
authorityInfoAccess
CA Issuers - URI:http://yr1.i.lencr.org/
subjectAltName
DNS:autoconfig.lebenohnedich.de, DNS:autodiscover.lebenohnedich.de, DNS:autodiscover.testmail.knipp.de, DNS:post.knipp.de
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/11.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 94:4E:43:87:FA:EC:C1:EF:81:F3:19:24:26:A8:18:65: 01:C7:D3:5F:38:02:01:3F:72:67:7D:55:37:2E:19:D8 Timestamp : Sep 18 19:47:49.683 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:12:03:CD:33:97:E9:43:80:B4:59:CC:44: E4:8F:20:A3:03:57:DC:BC:CE:05:25:5E:20:4C:B0:8B: A0:A5:94:D7:02:21:00:CB:14:8B:8B:52:BC:1F:8C:04: C0:E7:F3:4A:2B:13:6B:12:54:05:A0:F6:0F:F0:66:2A: 98:40:87:B6:A6:9B:44 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : A2:81:00:18:73:4E:17:6E:1D:47:E0:95:40:F3:81:BA: 54:66:97:CD:63:A8:43:50:71:6E:B8:09:4E:DA:F1:0D Timestamp : Sep 18 19:47:50.654 2026 GMT Extensions: 00:00:05:00:0F:41:79:00 Signature : ecdsa-with-SHA256 30:46:02:21:00:D0:21:30:0E:DC:3A:B5:B8:D5:47:27: 54:30:BE:78:5C:98:CF:11:80:19:BF:B2:04:17:40:83: 50:42:70:9D:26:02:21:00:A3:21:04:E9:8D:78:FB:C8: 83:AA:F0:F5:ED:41:DB:EB:83:6A:F8:DC:8B:55:E3:BA: FD:3C:3D:31:13:A9:00:62
-----BEGIN CERTIFICATE-----
MIIGUTCCBTmgAwIBAgISBhK0P7Y4rck8OVEw8NYrkOkKMA0GCSqGSIb3DQEBCwUA
MDMxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MQwwCgYDVQQD
EwNZUjEwHhcNMjYwOTE4MTg0OTE5WhcNMjYxMjE3MTg0OTE4WjAYMRYwFAYDVQQD
Ew1wb3N0LmtuaXBwLmRlMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA
8t3YOoQfmnEq66aolY5BEWQaO0v06crQ3xVF0cf3AOtZDPokhub9BybzXIvxwYcW
m/JX+tiizLc7yoiCu0KP7zkG/Ry3cWf9KXYLWXqrAFnLsstCdt/twXTu7vMivPrd
ztFlbAjrW2je5ty6c4OlZlEMfXkzCEgNHcvZA8N+k3zMslGW8RZsP2ccGEVDL/sW
fstMJm+SZzJwVL+Dlk3ylWa0jjpaaJLgZ0E7kbCZYZOmNJuz6jxjxh9diqhYY1pX
bNIdK+vt77nbj8kDVJ/bYuKFBiIdgrAKne41/ZzRcXQb52zx7ATnST5SuZUIMs2j
wG2nhXnG9lCAaTpi9PcU4X6umkiWf2z99kivLfG6neKvTWPlijJEds5VmMU7ePjy
L+ZuRVw6HR4hrDSMfNgkRneLkD9KhJY1xuxcoizEsKSWFtosdaD3eJwBsS4ZovEO
8smtFwWU3NhAGvxfnkYDHYYUU2lyfKDTyQa4jBng1zW4WNV6/l5nzfjPxS8huzir
2edjxD877XT9IkyMynVZ/1ji9SCe6ay2wg4oPL7429Dew95OF8wstzt4Jpj9NUer
IlOeVmVhUUCUrXoFPTpubGmLaV5vNFcbBFU02uJtF+CTenj1MnAeIClxYfnKSVL5
130bFTrTxjuwoqezxdmISUdzwjCTiXzUDk3fk5V4VvUCAwEAAaOCAngwggJ0MA4G
A1UdDwEB/wQEAwIFoDATBgNVHSUEDDAKBggrBgEFBQcDATAMBgNVHRMBAf8EAjAA
MB0GA1UdDgQWBBTKUObTJCAq+SPiNSXCgZ9ohxOlQjAfBgNVHSMEGDAWgBQfLzW+
RhSCzUCxrnksVXj699Ro+zAzBggrBgEFBQcBAQQnMCUwIwYIKwYBBQUHMAKGF2h0
dHA6Ly95cjEuaS5sZW5jci5vcmcvMHQGA1UdEQRtMGuCG2F1dG9jb25maWcubGVi
ZW5vaG5lZGljaC5kZYIdYXV0b2Rpc2NvdmVyLmxlYmVub2huZWRpY2guZGWCHmF1
dG9kaXNjb3Zlci50ZXN0bWFpbC5rbmlwcC5kZYINcG9zdC5rbmlwcC5kZTATBgNV
HSAEDDAKMAgGBmeBDAECATAuBgNVHR8EJzAlMCOgIaAfhh1odHRwOi8veXIxLmMu
bGVuY3Iub3JnLzExLmNybDCCAQ0GCisGAQQB1nkCBAIEgf4EgfsA+QB2AJROQ4f6
7MHvgfMZJCaoGGUBx9NfOAIBP3JnfVU3LhnYAAABoLYPlTMAAAQDAEcwRQIgEgPN
M5fpQ4C0WcxE5I8gowNX3LzOBSVeIEywi6CllNcCIQDLFIuLUrwfjATA5/NKKxNr
ElQFoPYP8GYqmECHtqabRAB/AKKBABhzThduHUfglUDzgbpUZpfNY6hDUHFuuAlO
2vENAAABoLYPmP4ACAAABQAPQXkABAMASDBGAiEA0CEwDtw6tbjVRydUML54XJjP
EYAZv7IEF0CDUEJwnSYCIQCjIQTpjXj7yIOq8PXtQdvrg2r43ItV47r9PD0xE6kA
YjANBgkqhkiG9w0BAQsFAAOCAQEALXzfJXy28t3BixZ7M85Fx3dTbyn/aOlbHzlj
0Mc3xz6v0FbBrNwNtthxSKlt0kAI0pXnuPXgqIrdPWOWk1g/jAyFvwBWcfHa+M6q
1S/omvukcaAatY5dhFv5mhgF4B1sb3C/Bmn2NzUL/41t7yPCBBFosOBaHN4ha2qq
SA50Wj96cUNMp7VuqkBJIF7E24tvAE5c0CtBc1ggrhKV9qgjwyOgsDNa2l0O006e
h771xZdZk0nxnsbFM8Ls2V6bVHv/60amUdZtNmMcnmir2cPca7VJ5T7Jeg2pPPPU
2T5znnlWuRgXLOcWsZCM6tg4LSqo60B+CzGAYhFna5Nh16a6Sw==
-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-09-23T02:08:15+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YR1
Issuer
C=US O=ISRG CN=Root YR
Valid from
2025-09-03T00:00:00+00:00
Expires
2028-09-02T23:59:59+00:00
Days remaining
710
Serial (hex)
A20253F15F2691C05DC1CE13B9BCCA4E
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

13:94:96:34:D9:9C:D6:FD:6A:A8:0B:C0:34:FE:FA:CC:EB:19:69:FE:EF:98:65:86:71:3E:CD:BB:05:75:8D:3F
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
1F:2F:35:BE:46:14:82:CD:40:B1:AE:79:2C:55:78:FA:F7:D4:68:FB
authorityKeyIdentifier
DE:E7:5B:60:D0:22:6D:40:28:7D:3F:0D:01:FE:A4:B5:52:B4:51:94
authorityInfoAccess
CA Issuers - URI:http://yr.i.lencr.org/
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr.c.lencr.org/ 
-----BEGIN CERTIFICATE-----
MIIE2zCCAsOgAwIBAgIRAKICU/FfJpHAXcHOE7m8yk4wDQYJKoZIhvcNAQELBQAw
LjELMAkGA1UEBhMCVVMxDTALBgNVBAoTBElTUkcxEDAOBgNVBAMTB1Jvb3QgWVIw
HhcNMjUwOTAzMDAwMDAwWhcNMjgwOTAyMjM1OTU5WjAzMQswCQYDVQQGEwJVUzEW
MBQGA1UEChMNTGV0J3MgRW5jcnlwdDEMMAoGA1UEAxMDWVIxMIIBIjANBgkqhkiG
9w0BAQEFAAOCAQ8AMIIBCgKCAQEAoVi8X2xCYgMXvJxNPKp/oF13UMgmPABB07VC
LNDtoXmt9luEZNJSBV10VyT1Pz6LD8Zq1d2gc43WNl1AdRrj4sEnazbOiz0nPpmG
Bp2hui49oZtDIY6wdKeZAi5BbNU20CH6RSBBMLSQ9cXrH8dxdv4PAJ45ssGML68U
SE3BsjC2a6cAN9L5CgXVIQi5tfNiTPoFZZ3S0OlXqLmmtdV95udWAb5b6e/F49Di
CsH0Y00Ag72BVIb1hzynmKe+X0mERBTtsb3BwmpV9ipeBjMLoR/D9cHxHQCWoi5l
TmXwY015J5rGelz1nZjJuxc2kioaX29XJBnhMkP531rSdG5uMwIDAQABo4HuMIHr
MA4GA1UdDwEB/wQEAwIBhjATBgNVHSUEDDAKBggrBgEFBQcDATASBgNVHRMBAf8E
CDAGAQH/AgEAMB0GA1UdDgQWBBQfLzW+RhSCzUCxrnksVXj699Ro+zAfBgNVHSME
GDAWgBTe51tg0CJtQCh9Pw0B/qS1UrRRlDAyBggrBgEFBQcBAQQmMCQwIgYIKwYB
BQUHMAKGFmh0dHA6Ly95ci5pLmxlbmNyLm9yZy8wEwYDVR0gBAwwCjAIBgZngQwB
AgEwJwYDVR0fBCAwHjAcoBqgGIYWaHR0cDovL3lyLmMubGVuY3Iub3JnLzANBgkq
hkiG9w0BAQsFAAOCAgEA0+zvMq3kHig1ddTmmm+RibTr9/RpX7k4buanMMRqbV/y
IvP82zAHN3mvaw+cASuVsdpd0ikjhr4hnhJQLQOzOp2ccKrsdGOAgo0vddeISFAq
EWEV4lmUM3vFF796up+bSgmJ1u6RupDCMxDgF8M3eLvGuj6L0lu3zkQ0KuQLnKxL
tB0oQqn1Idg5CuuGpMvQzk29Pa3D/qHurc0EIM9SxukQuJqq63lxsYyRQFU8yMBO
hq1w5LbfaWNRrz1uklOfI/pYkAb2E2MTZrAMQkBIE2S8Jt1F8gRc96o/xOsrgvSk
a84AisX6xq1lz1Z7jGvrnXc4TMcjxZTjiTaihcYI1JIXZiLtEMSCa5l3cu8YWd6z
dLRQlqRdclVjuQfNHawRJ6GWlkK0QJosivTKwdBw3KxEtzGo8yMHERbsy57gP1UX
HOMcmZYQC0gtyR3SxfenIM/MxC3Ia2Ypab/kQ/CTnlIn2KQ5JUC6NYrGCbhFN9bp
5lKJStEwCUnLpntcrXk5XVDCNv/5RyWpRThkGOV7GetKkQ0qAY8hCzWK6oqnAhDZ
cjlYVdWfqOw3DIOX6EDNBgAqHarRVxyF9QZdOaXSyPJ0ueD2BYJEBgaCGQ8rAaU/
Qc123V5LTXDZW4CcsPBDyhy4v+c8hClAyw/IkJlfBqxB9D+/wvIMHgECZ4ptP6o=
-----END CERTIFICATE-----

Chain certificate 2

Subject
C=US O=ISRG CN=Root YR
Issuer
C=US O=Internet Security Research Group CN=ISRG Root X1
Valid from
2026-05-13T00:00:00+00:00
Expires
2032-09-02T23:59:59+00:00
Days remaining
2171
Serial (hex)
F24B6D17F9D9AD7CB1C9FEA78782699F
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

07:26:39:D0:B1:40:D5:BF:FA:E1:6A:D9:C3:F6:CC:60:86:04:06:21:F5:1E:E6:1A:6D:46:A8:91:5C:07:CF:76
Certificate extensions & PEM
keyUsage
Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE
subjectKeyIdentifier
DE:E7:5B:60:D0:22:6D:40:28:7D:3F:0D:01:FE:A4:B5:52:B4:51:94
authorityKeyIdentifier
79:B4:59:E6:7B:B6:E5:E4:01:73:80:08:88:C8:1A:58:F6:E9:9B:6E
authorityInfoAccess
CA Issuers - URI:http://x1.i.lencr.org/
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://x1.c.lencr.org/ 
-----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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