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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

TLSv1.3

osn.de · 194.45.27.133:443

Verified

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

Subject
CN=osn.de
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-09-27T00:33:21+00:00
Expires
2026-12-26T00:33:20+00:00
Days remaining
77
Serial (hex)
05A0DE8C73E13222B2FA648D99E939898727
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:*.osn.de, DNS:osn.de

SHA-256 fingerprint

97:EA:0E:F0:92:59:57:38:B6:D4:04:AB:0F:9A:5A:5B:FD:EA:2F:7B:87:0A:7B:0F:EE:81:0D:AD:45:7D:68:FD
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
7E:BC:F9:5E:53:D9:32:F3:BB:65:A3:20:85:8F:41:6A:32:9D:2D:3C
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:*.osn.de, DNS:osn.de
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/40.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : D7:6D:7D:10:D1:A7:F5:77:C2:C7:E9:5F:D7:00:BF:F9: 82:C9:33:5A:65:E1:D0:B3:01:73:17:C0:C8:C5:69:77 Timestamp : Sep 27 01:31:51.679 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:61:62:31:51:11:CD:77:04:D4:37:45:9F: 72:78:AC:58:3F:53:5A:89:2C:F1:24:12:E3:93:ED:E3: 6A:CC:BC:14:02:21:00:85:9E:D9:DD:51:03:ED:AD:93: 22:DB:2C:74:D8:71:58:57:EB:91:E2:7F:D1:91:D0:2C: 6C:E4:92:71:B1:3A:EE Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 26:E3:64:6E:58:69:21:23:BC:34:3F:47:24:35:9B:37: 92:CD:24:5A:88:D8:15:D3:93:33:FD:99:18:AB:47:23 Timestamp : Sep 27 01:31:49.137 2026 GMT Extensions: 00:00:05:00:46:E5:65:51 Signature : ecdsa-with-SHA256 30:46:02:21:00:EA:AD:26:6E:26:B8:9F:46:D8:3F:AE: 42:EC:3F:8B:0A:50:55:87:07:45:8B:BC:46:D5:1C:8E: AF:B2:1F:71:C7:02:21:00:E9:13:77:55:B8:2B:84:27: 49:BC:A0:C2:7D:28:EE:29:F2:B3:C1:7C:53:BA:4A:81: 00:4D:F2:82:C3:D5:99:D7
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-10-09T05:22:48+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
694
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-----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=
-----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
2155
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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