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

pknu.ac.kr · 203.250.126.211:443

Verified

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

Subject
CN=*.pknu.ac.kr
Issuer
C=GB O=Sectigo Limited CN=Sectigo Public Server Authentication CA DV R36
Valid from
2026-03-11T00:00:00+00:00
Expires
2027-04-10T23:59:59+00:00
Days remaining
167
Serial (hex)
F9E6270CCE5A3500C7295272B3913BBE
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:*.pknu.ac.kr, DNS:pknu.ac.kr

SHA-256 fingerprint

B0:7D:67:C3:41:CB:44:B6:31:31:81:71:4A:6D:5B:D8:55:15:E5:30:C4:CE:84:AA:A7:6C:88:B8:FE:D1:BF:1A
Certificate extensions & PEM
authorityKeyIdentifier
68:C0:12:16:18:0E:AF:CE:F6:87:A6:32:57:A3:46:51:5D:CB:07:27
subjectKeyIdentifier
38:07:96:7E:6F:A4:DD:3B:80:05:69:BC:5C:A6:2E:56:53:19:5D:A5
keyUsage
Digital Signature, Key Encipherment
basicConstraints
CA:FALSE
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
certificatePolicies
Policy: 1.3.6.1.4.1.6449.1.2.2.7 CPS: https://sectigo.com/CPS Policy: 2.23.140.1.2.1
authorityInfoAccess
CA Issuers - URI:http://crt.sectigo.com/SectigoPublicServerAuthenticationCADVR36.crt OCSP - URI:http://ocsp.sectigo.com
subjectAltName
DNS:*.pknu.ac.kr, DNS:pknu.ac.kr
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1C:9F:68:2C:E9:FA:F0:45:69:50:F8:1B:96:8A:87:DD: DB:32:10:D8:4C:E6:C8:B2:E3:82:52:4A:C4:CF:59:9F Timestamp : Mar 11 04:25:58.554 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:72:28:44:4F:B2:46:47:B8:67:45:9A:86: 69:1B:3B:D0:77:71:0B:3B:1F:3B:FA:F5:65:F5:04:51: BD:AF:CC:D1:02:21:00:E1:3F:35:0B:77:86:70:47:ED: 47:CC:C3:38:63:2B:67:82:6F:F8:2A:66:FB:C5:B4:DD: 13:B8:ED:11:FD:5E:E7 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 8E:CA:47:0B:AC:DE:6A:F3:A2:06:B0:A4:7A:84:B7:46: FE:1F:C6:BF:95:3E:25:E6:9B:4E:E4:02:48:F3:C6:E8 Timestamp : Mar 11 04:25:58.774 2026 GMT Extensions: 00:00:05:00:03:14:B9:5B Signature : ecdsa-with-SHA256 30:46:02:21:00:A0:DE:12:66:91:DE:4D:BB:58:99:CB: 16:CD:66:BE:0C:9C:F2:6B:47:A7:5A:22:76:56:9E:A6: BE:E5:57:6F:34:02:21:00:AE:EB:F3:7A:B0:16:5B:F9: EF:5A:42:CA:5C:1E:1E:E3:A4:DE:89:23:A6:CE:C4:1D: AC:FF:EE:79:81:F1:6E:1A Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 59:6E:6C:33:86:94:B2:59:72:A2:56:C8:A0:E8:DD:90: 4A:76:E8:08:3D:DA:87:3B:01:08:38:28:14:3C:EE:59 Timestamp : Mar 11 04:25:58.434 2026 GMT Extensions: 00:00:05:00:00:36:92:B2 Signature : ecdsa-with-SHA256 30:46:02:21:00:AA:A7:3A:28:F7:E0:09:78:CD:36:E2: 59:A8:E5:90:87:D0:D4:FD:D6:11:4C:F1:42:E6:59:7B: 7A:16:C1:0A:BD:02:21:00:D3:D8:66:45:24:B4:D4:8E: 65:31:6F:1A:C0:95:F3:45:F8:9F:75:56:2C:DF:0D:40: 25:B1:BB:76:DA:7B:DA:80
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-10-25T18:11:28+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=GB O=Sectigo Limited CN=Sectigo Public Server Authentication CA DV R36
Issuer
C=GB O=Sectigo Limited CN=Sectigo Public Server Authentication Root R46
Valid from
2021-03-22T00:00:00+00:00
Expires
2036-03-21T23:59:59+00:00
Days remaining
3435
Serial (hex)
397A66CC2756362E0DAA87CA6EABE3B1
Signature
RSA-SHA384
Public key
RSA 3072

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

8C:54:C3:34:B6:6B:A4:E4:26:77:2A:F4:A3:F9:13:6C:19:A1:AE:C7:29:FD:B2:8C:53:5C:07:A5:A4:EF:22:E0
Certificate extensions & PEM
authorityKeyIdentifier
56:73:58:64:95:F9:92:1A:B0:12:2A:04:62:79:A1:40:15:88:21:49
subjectKeyIdentifier
68:C0:12:16:18:0E:AF:CE:F6:87:A6:32:57:A3:46:51:5D:CB:07:27
keyUsage
Digital Signature, Certificate Sign, CRL Sign
basicConstraints
CA:TRUE, pathlen:0
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
certificatePolicies
Policy: X509v3 Any Policy Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://crl.sectigo.com/SectigoPublicServerAuthenticationRootR46.crl
authorityInfoAccess
CA Issuers - URI:http://crt.sectigo.com/SectigoPublicServerAuthenticationRootR46.p7c OCSP - URI:http://ocsp.sectigo.com
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Chain certificate 2

Subject
C=GB O=Sectigo Limited CN=Sectigo Public Server Authentication Root R46
Issuer
C=US ST=New Jersey L=Jersey City O=The USERTRUST Network CN=USERTrust RSA Certification Authority
Valid from
2021-03-22T00:00:00+00:00
Expires
2038-01-18T23:59:59+00:00
Days remaining
4103
Serial (hex)
D27FBBC1DE359E5216AD6149586099C4
Signature
RSA-SHA384
Public key
RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

92:F3:51:BF:3D:54:16:4D:FA:8D:D8:F9:E1:13:9D:31:50:34:97:86:48:5D:2B:9E:EC:D0:0E:29:71:C1:E6:C5
Certificate extensions & PEM
authorityKeyIdentifier
53:79:BF:5A:AA:2B:4A:CF:54:80:E1:D8:9B:C0:9D:F2:B2:03:66:CB
subjectKeyIdentifier
56:73:58:64:95:F9:92:1A:B0:12:2A:04:62:79:A1:40:15:88:21:49
keyUsage
Digital Signature, Certificate Sign, CRL Sign
basicConstraints
CA:TRUE
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
certificatePolicies
Policy: X509v3 Any Policy
crlDistributionPoints
Full Name: URI:http://crl.usertrust.com/USERTrustRSACertificationAuthority.crl
authorityInfoAccess
OCSP - URI:http://ocsp.usertrust.com
-----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 →