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

TLSv1.2

zero-sys.net · 95.216.26.215:443

Verified

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

Subject
CN=ubloit.zero-sys.net
Issuer
C=US O=Let's Encrypt CN=YE2
Valid from
2026-08-28T18:45:25+00:00
Expires
2026-11-26T18:45:24+00:00
Days remaining
44
Serial (hex)
053027CAD4654887FF0E79F6A184EDCCB635
Signature
ecdsa-with-SHA384
Public key
EC 256 prime256v1

Subject alternative names (SAN)

DNS:cl.freie-schule-elbehavelland.de, DNS:cl.zero-sys.de, DNS:cl.zero-sys.net, DNS:cl2.zero-sys.de, DNS:cl2.zero-sys.net, DNS:cloud.freie-schule-elbehavelland.de, DNS:imap.zero-sys.net, DNS:mail.zero-sys.net, DNS:mail2.zero-sys.net, DNS:mx.zero-sys.net, DNS:ncloud.freie-schule-elbehavelland.de, DNS:oo.freie-schule-elbehavelland.de, DNS:oo.zero-sys.de, DNS:oo.zero-sys.net, DNS:repo.zero-sys.net, DNS:repo2.zero-sys.net, DNS:smtp.zero-sys.net, DNS:ubloit.zero-sys.net, DNS:www.zero-sys.de, DNS:www.zero-sys.net, DNS:www2.zero-sys.de, DNS:www2.zero-sys.net, DNS:zero-sys.de, DNS:zero-sys.net

SHA-256 fingerprint

06:E5:B5:59:4C:24:C0:AB:5E:50:51:52:E4:FB:E0:12:00:BD:54:D6:60:5B:8F:83:5B:A0:DC:CA:AC:DB:93:6F
Certificate extensions & PEM
keyUsage
Digital Signature
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
2D:5D:A6:94:90:FB:FA:FE:7E:7C:E0:B6:F1:6E:1C:1B:93:5A:68:49
authorityKeyIdentifier
B9:59:F2:8E:CF:22:F0:86:D3:37:48:FF:76:14:18:BA:82:D8:55:87
authorityInfoAccess
CA Issuers - URI:http://ye2.i.lencr.org/
subjectAltName
DNS:cl.freie-schule-elbehavelland.de, DNS:cl.zero-sys.de, DNS:cl.zero-sys.net, DNS:cl2.zero-sys.de, DNS:cl2.zero-sys.net, DNS:cloud.freie-schule-elbehavelland.de, DNS:imap.zero-sys.net, DNS:mail.zero-sys.net, DNS:mail2.zero-sys.net, DNS:mx.zero-sys.net, DNS:ncloud.freie-schule-elbehavelland.de, DNS:oo.freie-schule-elbehavelland.de, DNS:oo.zero-sys.de, DNS:oo.zero-sys.net, DNS:repo.zero-sys.net, DNS:repo2.zero-sys.net, DNS:smtp.zero-sys.net, DNS:ubloit.zero-sys.net, DNS:www.zero-sys.de, DNS:www.zero-sys.net, DNS:www2.zero-sys.de, DNS:www2.zero-sys.net, DNS:zero-sys.de, DNS:zero-sys.net
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://ye2.c.lencr.org/54.crl
ct_precert_scts
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 : Aug 28 19:43:55.600 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:C0:A4:8B:07:32:5B:53:A8:55:18:12: 14:AA:BB:D2:FC:8A:24:1B:B1:93:A7:A6:14:E4:16:57: FC:0E:EA:BB:C9:02:21:00:A4:5F:AD:EE:F7:9B:02:7E: 6F:86:76:99:A6:F4:5E:5E:2F:C2:C2:7F:30:BB:72:50: 25:4A:4C:E2:70:B0:A9:A6 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 28 19:43:56.369 2026 GMT Extensions: 00:00:05:00:39:D0:4A:1B Signature : ecdsa-with-SHA256 30:46:02:21:00:D3:73:4F:EE:22:55:AF:14:F1:A8:61: 12:F7:46:95:7C:F8:BA:FB:58:21:48:7A:24:C4:09:71: 43:35:44:59:65:02:21:00:B1:BD:A3:C3:C0:99:75:D4: E6:84:81:61:E3:90:BF:A1:66:69:B0:31:D8:0B:3D:63: FA:31:BD:80:5D:04:E8:99
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: ECDHE-ECDSA-AES128-GCM-SHA256 · Checked 2026-10-12T20:55:40+00:00

Server-presented chain · 3 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YE2
Issuer
C=US O=ISRG CN=Root YE
Valid from
2025-09-03T00:00:00+00:00
Expires
2028-09-02T23:59:59+00:00
Days remaining
691
Serial (hex)
4DF3B15DD6C0784C507CD37B58E6F115
Signature
ecdsa-with-SHA384
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

97:65:8D:E8:C6:8D:FA:98:AC:E1:E5:02:8A:63:D5:4A:1A:AE:91:1B:3E:21:47:10:76:C6:85:0C:D0:8C:BA:B4
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
B9:59:F2:8E:CF:22:F0:86:D3:37:48:FF:76:14:18:BA:82:D8:55:87
authorityKeyIdentifier
A3:C8:26:5A:8E:A1:4C:D0:35:63:FC:9B:23:C8:3A:AE:56:F3:4F:56
authorityInfoAccess
CA Issuers - URI:http://ye.i.lencr.org/
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://ye.c.lencr.org/ 
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Chain certificate 2

Subject
C=US O=ISRG CN=Root YE
Issuer
C=US O=Internet Security Research Group CN=ISRG Root X2
Valid from
2026-05-13T00:00:00+00:00
Expires
2032-09-02T23:59:59+00:00
Days remaining
2152
Serial (hex)
872165FC34B6E5FBA8ADD5B3705FB53A
Signature
ecdsa-with-SHA384
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

0F:C0:90:1C:CA:2B:AE:9E:9F:DB:B0:2D:50:D0:2F:10:94:F7:B3:66:72:08:69:91:B9:E8:97:62:6D:C4:85:F0
Certificate extensions & PEM
keyUsage
Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE
subjectKeyIdentifier
A3:C8:26:5A:8E:A1:4C:D0:35:63:FC:9B:23:C8:3A:AE:56:F3:4F:56
authorityKeyIdentifier
7C:42:96:AE:DE:4B:48:3B:FA:92:F8:9E:8C:CF:6D:8B:A9:72:37:95
authorityInfoAccess
CA Issuers - URI:http://x2.i.lencr.org/
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://x2.c.lencr.org/ 
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Chain certificate 3

Subject
C=US O=Internet Security Research Group CN=ISRG Root X2
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
2152
Serial (hex)
6C8F1DC727C7117F7BAF853AC980F9CD
Signature
RSA-SHA256
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

EE:5F:7A:BD:69:81:BB:02:55:63:2C:D8:F4:92:83:45:1B:4B:18:84:4D:12:04:0B:44:EE:00:F0:7B:8F:E2:C6
Certificate extensions & PEM
keyUsage
Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
basicConstraints
CA:TRUE
subjectKeyIdentifier
7C:42:96:AE:DE:4B:48:3B:FA:92:F8:9E:8C:CF:6D:8B:A9:72:37:95
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-----
MIIEcDCCAligAwIBAgIQbI8dxyfHEX97r4U6yYD5zTANBgkqhkiG9w0BAQsFADBP
MQswCQYDVQQGEwJVUzEpMCcGA1UEChMgSW50ZXJuZXQgU2VjdXJpdHkgUmVzZWFy
Y2ggR3JvdXAxFTATBgNVBAMTDElTUkcgUm9vdCBYMTAeFw0yNjA1MTMwMDAwMDBa
Fw0zMjA5MDIyMzU5NTlaME8xCzAJBgNVBAYTAlVTMSkwJwYDVQQKEyBJbnRlcm5l
dCBTZWN1cml0eSBSZXNlYXJjaCBHcm91cDEVMBMGA1UEAxMMSVNSRyBSb290IFgy
MHYwEAYHKoZIzj0CAQYFK4EEACIDYgAEzZvVn4CDCuwJSvMWSj5cz3es3mcFDR0H
ttwW+1qLFNvicWDEukWVEYmO6gbf9yoWHKS5xcUy4APgHoIYOIvXRdgKam7mAHf7
AlF9ItgKbppbd9/w+kHsOdx1ymgHDB/qo4H1MIHyMA4GA1UdDwEB/wQEAwIBBjAd
BgNVHSUEFjAUBggrBgEFBQcDAQYIKwYBBQUHAwIwDwYDVR0TAQH/BAUwAwEB/zAd
BgNVHQ4EFgQUfEKWrt5LSDv6kviejM9ti6lyN5UwHwYDVR0jBBgwFoAUebRZ5nu2
5eQBc4AIiMgaWPbpm24wMgYIKwYBBQUHAQEEJjAkMCIGCCsGAQUFBzAChhZodHRw
Oi8veDEuaS5sZW5jci5vcmcvMBMGA1UdIAQMMAowCAYGZ4EMAQIBMCcGA1UdHwQg
MB4wHKAaoBiGFmh0dHA6Ly94MS5jLmxlbmNyLm9yZy8wDQYJKoZIhvcNAQELBQAD
ggIBAD2/e9frmMxNpCV03qUHegg+MV2wz9644YoXdqtH8RyWYcBO7xfjjGEXdU1e
/o0OkEFiynUCOSIk/vLLo7ttz6CPAeNlWfC0XNkoGeWgK6jjXvozBaGuGH5n0Ufo
shMeWTuURqNN5G00sSXDTBrpp2+mgvdZQjb8K11TYMA25QA+YHNfbIEL0BniAhKS
2gsnJjSzrdZLI+EZ7SEyqdR2rkjd1KutLDU+n3TFyxjniZVGur4YlhMP3mY/dV95
IruAkkjOZier6hGBdEgZXXvaCz9u9iVEadsIE75pAGL8oHV5vxdARDiotRpul1IN
/UZwzAbrfUFcw1HkAcYD/mlZfnQ2ieCF2MS7j3Vhv7JPDKp45fmykmzYNSrumRW0
upFFKDBOoF7hsOb7oLyHS+Uft6jOUfOrogj8YUx38hKb2K20r42OgsSdDdxdeYWc
MS3Sb6mwJeSZEYxJ2gaXnDSPaKhhrNkYwljyVQyr4Nq+MEJytXNTnHqaAcrNwZlV
pcJL1KBnMrMjP7eanvUwL3FYj3cF17jtboLt7gLoi4+2rWZFvn+w54jmd/FIuhhZ
cEaU/wvU6BUNMtcVquVGHp7itQeDth5j+XL3j4WJ2SABwzUl6OeYdgpIt/ITZa+p
TT0mQ/r5XyA4MEAiabn7XJjvCERlF2dcn2wqJw+CreTkkQ2R
-----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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