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

mailgate01.omg.de · 109.239.193.3:443

Verified

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

Subject
CN=mailgate01.omg.de
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-09-24T01:52:31+00:00
Expires
2026-12-23T01:52:30+00:00
Days remaining
63
Serial (hex)
066BC277855A6CBD3E4B8F63783986555CD5
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:mailgate01.omg.de, DNS:mta-sts.omg.de

SHA-256 fingerprint

29:2B:0B:BB:D4:66:80:57:8F:8C:20:39:59:1F:62:DC:52:6A:F8:09:8F:DF:F5:ED:0A:39:61:3F:5D:08:59:22
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
F6:07:B1:C8:DD:C4:EE:A7:32:F9:20:37:A9:E5:F7:9F:0C:AA:F6:A3
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:mailgate01.omg.de, DNS:mta-sts.omg.de
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/86.crl
ct_precert_scts
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 24 02:50:58.879 2026 GMT Extensions: 00:00:05:00:45:BB:17:AE Signature : ecdsa-with-SHA256 30:45:02:21:00:8E:49:C1:D1:E4:BF:D3:CF:3C:87:EC: 54:D6:DB:37:EB:52:9A:97:A0:7A:05:BE:67:F3:8E:88: 62:1D:E9:CC:0D:02:20:5C:7E:A8:01:1B:F7:1D:4B:C1: B7:A7:A0:3E:C9:0D:D0:4E:20:C2:37:B5:0F:F9:6E:76: 39:AE:70:D3:ED:F4:21 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : CB:38:F7:15:89:7C:84:A1:44:5F:5B:C1:DD:FB:C9:6E: F2:9A:59:CD:47:0A:69:05:85:B0:CB:14:C3:14:58:E7 Timestamp : Sep 24 02:51:05.347 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:8E:05:1E:7A:E8:E3:52:96:69:D1:EB: B3:BD:0E:E4:91:49:C7:A8:7F:13:B0:2D:3A:BE:00:CC: A7:84:BD:CC:9E:02:20:4E:A2:9E:E8:B0:CB:0F:B4:AC: 65:26:BA:E7:B5:1E:13:BD:2E:AC:0E:1E:47:F8:E3:0E: 44:FC:7E:E0:54:3A:7A
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-10-20T05:27:35+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
683
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
2144
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 →