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

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
2026-07-31T00:45:07+00:00
Expires
2026-10-29T00:45:06+00:00
Days remaining
33
Serial (hex)
062065A3C3A4156F72BFB11E2447F5AB0651
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

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

SHA-256 fingerprint

32:19:70:CC:66:52:A8:6E:74:28:8A:D7:47:DF:96:B7:6E:32:9F:13:EE:1B:2D:51:FB:DA:25:5D:92:B5:CF:34
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
F6:22:B4:90:77:B7:64:9D:F3:CF:9B:BE:FF:34:ED:96:60:92:DD:BD
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/82.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : AF:67:88:3B:57:B0:4E:DD:8F:A6:D9:7E:F6:2E:A8:EB: 81:0A:C7:71:60:F0:24:5E:55:D6:0C:2F:E7:85:87:3A Timestamp : Jul 31 01:43:37.781 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:9C:AB:CD:D6:08:50:21:7F:0A:1C:C5: 20:CC:D1:41:DF:25:7A:36:4E:6C:B0:3A:9E:C6:2B:D8: D5:99:DF:76:5F:02:20:0F:38:DE:7E:8A:F7:E6:51:04: 00:A0:26:18:C0:D7:46:48:17:9C:DA:5E:28:5D:C6:89: 1B:12:E9:53:9F:CF:D1 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : A8:26:CB:E3:0A:C6:35:12:46:53:3F:E0:65:F1:4F:19: D9:6E:19:08:13:C4:1D:D9:6D:79:00:B3:12:3C:55:27 Timestamp : Jul 31 01:43:37.654 2026 GMT Extensions: 00:00:05:00:17:56:9C:FB Signature : ecdsa-with-SHA256 30:44:02:20:17:38:A1:07:74:D7:DD:E7:1D:43:9F:72: BE:9A:07:20:5A:F4:80:5F:FC:99:50:EB:A5:C8:C0:7B: A2:F7:B7:C0:02:20:0F:E1:0D:88:1B:D5:75:A9:80:FB: 89:91:FF:F9:93:0F:46:09:66:AE:D1:FB:D3:BD:87:5E: 92:79:88:24:C7:E1
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-09-25T17:19:50+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
708
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
2169
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

Registration / WHOIS →DNS records →