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

mx2.opteamax.de · 194.62.23.196:443

Verified
The certificate expires within 30 days.

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

Subject
CN=mx2.opteamax.de
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-08-02T21:04:34+00:00
Expires
2026-10-31T21:04:33+00:00
Days remaining
29
Serial (hex)
05DDB5DA0131C3834EEFD509EBE481D666A3
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:mx2.opteamax.de, DNS:sibi.fyi

SHA-256 fingerprint

D6:1C:CA:7B:56:02:F2:02:36:A8:71:DE:95:F4:15:16:D9:BF:11:41:82:32:A2:B9:8C:1E:04:01:33:88:5A:A0
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
DC:A6:0A:7C:CA:BC:12:EC:D5:2A:2F:DA:F2:A9:76:70:A9:E6:0B:85
authorityKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
authorityInfoAccess
CA Issuers - URI:http://yr2.i.lencr.org/
subjectAltName
DNS:mx2.opteamax.de, DNS:sibi.fyi
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/36.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1A:8B:9D:6B:0F:FE:BF:81:B4:79:39:C6:D2:31:0A:86: D6:D1:02:D4:F0:46:E2:18:2C:9D:E3:5F:5E:26:25:EF Timestamp : Aug 2 22:03:04.593 2026 GMT Extensions: 00:00:05:00:30:8C:7C:8C Signature : ecdsa-with-SHA256 30:45:02:20:38:3C:E5:BE:63:07:97:FA:F4:DA:8E:09: 42:B4:16:A5:3C:90:7F:9A:94:6C:76:66:72:9D:7A:A9: E6:97:AE:42:02:21:00:C4:29:92:0B:35:B1:A5:E6:1E: E4:1C:4A:4C:C4:59:DB:2B:80:C2:7D:54:93:08:C6:06: E0:F4:1C:6E:53:69:F7 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 : Aug 2 22:03:04.601 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:E3:72:2F:21:62:FB:AD:89:21:92:14: 45:6A:91:83:D6:FB:F0:AB:31:34:7A:84:CA:74:78:55: B1:28:E2:17:1B:02:20:7A:48:9D:3F:7D:5C:DA:27:C3: 70:B0:3B:C0:2A:F9:AB:74:29:14:81:51:74:F5:97:3C: 10:65:64:6F:21:74:39
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-10-02T17:37:48+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YR2
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
701
Serial (hex)
4EBD24947E24D394802D84A52FD5B319
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

23:8B:85:A0:09:9C:65:B9:70:47:7D:57:24:F1:A1:D4:75:CE:50:58:CF:FE:4E:FA:87:33:89:9B:DB:86:3C:47
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
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
2162
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 →