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

ost.ch · 146.136.212.33:443

Verified

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

Subject
CN=ost.ch
Issuer
C=US O=Let's Encrypt CN=YE1
Valid from
2026-09-25T05:09:04+00:00
Expires
2026-12-24T05:09:03+00:00
Days remaining
78
Serial (hex)
05F96AFF5599C8D0EF01AEA53FD7424B70E4
Signature
ecdsa-with-SHA384
Public key
EC 256 prime256v1

Subject alternative names (SAN)

DNS:alumni.ost.ch, DNS:alumniost.ch, DNS:digitallab.ost.ch, DNS:events.ost.ch, DNS:magazin.ost.ch, DNS:ost.ch, DNS:vote.hsr.ch, DNS:www.ost.ch, DNS:www.real.ost.ch, DNS:www.vote.hsr.ch, DNS:www.wpz.ch

SHA-256 fingerprint

51:9F:9E:3A:DD:DA:24:F4:B8:80:33:0A:46:EF:FE:CA:3E:C8:45:C6:91:76:89:6D:E2:88:C9:A7:3D:36:03:1A
Certificate extensions & PEM
keyUsage
Digital Signature
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
97:EA:CB:98:54:CA:37:64:99:C9:53:3D:A5:5E:88:E7:1E:C8:C9:6F
authorityKeyIdentifier
BB:20:CA:47:0B:FE:D7:E5:9C:F9:8F:09:2A:A3:8C:37:45:B1:BC:D8
authorityInfoAccess
CA Issuers - URI:http://ye1.i.lencr.org/
subjectAltName
DNS:alumni.ost.ch, DNS:alumniost.ch, DNS:digitallab.ost.ch, DNS:events.ost.ch, DNS:magazin.ost.ch, DNS:ost.ch, DNS:vote.hsr.ch, DNS:www.ost.ch, DNS:www.real.ost.ch, DNS:www.vote.hsr.ch, DNS:www.wpz.ch
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://ye1.c.lencr.org/101.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 94:4E:43:87:FA:EC:C1:EF:81:F3:19:24:26:A8:18:65: 01:C7:D3:5F:38:02:01:3F:72:67:7D:55:37:2E:19:D8 Timestamp : Sep 25 06:07:34.320 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:73:F0:5D:5B:59:BA:B8:3B:D3:CA:EC:86: 0A:9A:1B:47:5B:98:5D:FD:53:E6:EE:15:D6:DD:43:F1: A1:1C:78:6B:02:21:00:E0:F8:BB:27:BE:C9:E5:9E:31: 9D:C0:07:32:99:86:75:93:85:C4:3E:CF:C6:39:29:54: 80:FB:13:BB:90:84:B9 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 : Sep 25 06:07:35.379 2026 GMT Extensions: 00:00:05:00:44:F1:91:47 Signature : ecdsa-with-SHA256 30:45:02:20:62:B5:9A:7A:11:CE:96:B1:1E:03:87:7C: D9:ED:67:F0:64:82:4D:B8:27:67:EB:58:77:E4:E4:DE: 5C:10:D8:21:02:21:00:97:F9:A1:99:97:56:0C:1D:B5: 82:BB:95:4D:84:C6:33:C0:90:05:BB:C2:0F:80:C4:61: 66:A0:78:C0:E4:8C:84
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-10-06T08:42:36+00:00

Server-presented chain · 3 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YE1
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
697
Serial (hex)
5DDD70DD31F801C85C186A7A04B80AFE
Signature
ecdsa-with-SHA384
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

A2:37:2D:06:43:1E:97:16:36:5E:EE:D4:7E:C0:20:35:14:97:D1:82:FC:C0:38:E4:57:E5:81:68:A0:3C:AC:07
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
BB:20:CA:47:0B:FE:D7:E5:9C:F9:8F:09:2A:A3:8C:37:45:B1:BC:D8
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
2158
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
2158
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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