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
2026-07-25T20:34:18+00:00
Expires
2026-10-23T20:34:17+00:00
Days remaining
30
Serial (hex)
054A2EF9340A0232AEBE86257DAEB4B370A2
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

5F:A4:AD:EB:B9:2F:95:BF:A6:B9:0E:2B:2C:0F:94:00:28:B0:49:98:EA:98:53:89:78:F0:7D:94:9A:AB:4A:4D
Certificate extensions & PEM
keyUsage
Digital Signature
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
C3:54:65:B3:10:54:D6:8E:B4:05:E6:F2:2E:E5:99:00:5F:4B:01:97
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/35.crl
ct_precert_scts
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 : Jul 25 21:32:48.400 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:55:41:DF:EC:68:6E:FF:26:F1:9D:70:0B: 63:39:97:3F:53:AC:5B:21:F9:E0:41:FA:BD:14:C0:AB: 7B:3A:D7:36:02:21:00:D9:32:60:26:80:B3:2F:70:5D: 33:CF:0F:8D:8A:2B:0C:DA:74:EF:FC:92:80:E6:8E:76: 38:43:39:F0:D3:46:1C 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 25 21:32:49.287 2026 GMT Extensions: 00:00:05:00:16:31:99:CD Signature : ecdsa-with-SHA256 30:46:02:21:00:B2:A1:C7:C9:37:36:DC:50:BF:30:07: D0:66:8E:81:9C:08:AA:89:4F:EB:A6:20:78:59:BB:C9: 4A:63:C6:30:5B:02:21:00:90:7D:B8:06:4E:19:D8:4B: F3:33:5C:78:13:24:B4:AD:FC:D3:2D:FE:8B:6D:34:95: 62:79:CA:83:A4:ED:A0:F9
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-09-22T23:28:25+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
711
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-----
MIICizCCAhGgAwIBAgIQXd1w3TH4AchcGGp6BLgK/jAKBggqhkjOPQQDAzAuMQsw
CQYDVQQGEwJVUzENMAsGA1UEChMESVNSRzEQMA4GA1UEAxMHUm9vdCBZRTAeFw0y
NTA5MDMwMDAwMDBaFw0yODA5MDIyMzU5NTlaMDMxCzAJBgNVBAYTAlVTMRYwFAYD
VQQKEw1MZXQncyBFbmNyeXB0MQwwCgYDVQQDEwNZRTEwdjAQBgcqhkjOPQIBBgUr
gQQAIgNiAAQHZVB1/mimla2hfSurylScjPMZaOJXLz/NnAc2sylm8WDyhU9Ccp+z
ASQi5vSwGGJjSGklkD9fdPR8GpyDIOIjCEfrnbt/v+ZSEPLLEGbaM6EccDbN7p9x
teIm2Avf+ryjge4wgeswDgYDVR0PAQH/BAQDAgGGMBMGA1UdJQQMMAoGCCsGAQUF
BwMBMBIGA1UdEwEB/wQIMAYBAf8CAQAwHQYDVR0OBBYEFLsgykcL/tflnPmPCSqj
jDdFsbzYMB8GA1UdIwQYMBaAFKPIJlqOoUzQNWP8myPIOq5W809WMDIGCCsGAQUF
BwEBBCYwJDAiBggrBgEFBQcwAoYWaHR0cDovL3llLmkubGVuY3Iub3JnLzATBgNV
HSAEDDAKMAgGBmeBDAECATAnBgNVHR8EIDAeMBygGqAYhhZodHRwOi8veWUuYy5s
ZW5jci5vcmcvMAoGCCqGSM49BAMDA2gAMGUCMQDgjUEahFT/h3DRakqiPZpLvPgf
Zwkt6K2EOMmh1nvEzl83eMLYcod4GCl3b0J1Nn0CMBNYmEQJb4CEG5WoOe7aRn/L
VKu6saHmHEynI7ysIPd8zQsK1HdmhlHKlw9Z5GpGvA==
-----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
2172
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
2172
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-----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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

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