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

bts.sk · 194.160.23.4:443

Verified

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

Subject
C=SK L=Bratislava O=Slovenská technická univerzita v Bratislave CN=bts.sk
Issuer
C=GR O=Hellenic Academic and Research Institutions CA CN=GEANT TLS RSA 1
Valid from
2025-12-05T10:18:28+00:00
Expires
2026-12-05T10:18:28+00:00
Days remaining
72
Serial (hex)
1A9608B7176501FED79E26AEBBE1A49B
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:bts.sk, DNS:www.bts.sk, DNS:mail.bts.sk, DNS:webmail.bts.sk

SHA-256 fingerprint

E8:7F:C2:EF:43:B0:FC:ED:7E:03:CB:01:26:FA:41:89:22:D4:D3:A0:AA:EB:E5:F2:E8:16:1D:18:69:33:7A:30
Certificate extensions & PEM
basicConstraints
CA:FALSE
authorityKeyIdentifier
86:01:72:3F:8C:A9:70:E2:31:06:53:16:CE:01:5F:5B:79:C8:3C:3B
authorityInfoAccess
CA Issuers - URI:http://crt.harica.gr/HARICA-GEANT-TLS-R1.cer OCSP - URI:http://ocsp-tls.harica.gr
subjectAltName
DNS:bts.sk, DNS:www.bts.sk, DNS:mail.bts.sk, DNS:webmail.bts.sk
certificatePolicies
Policy: 2.23.140.1.2.2 Policy: 0.4.0.2042.1.7 Policy: 1.3.6.1.4.1.26513.1.1.1.2
extendedKeyUsage
TLS Web Client Authentication, TLS Web Server Authentication
crlDistributionPoints
Full Name: URI:http://crl.harica.gr/HARICA-GEANT-TLS-R1.crl
subjectKeyIdentifier
AB:13:55:B4:FB:C9:A4:8E:24:60:DF:88:17:E7:AA:6A:BB:53:6E:26
keyUsage
Digital Signature, Key Encipherment
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : AF:67:88:3B:57:B0:4E:DD:8F:A6:D9:7E:F6:2E:A8:EB: 81:0A:C7:71:60:F0:24:5E:55:D6:0C:2F:E7:85:87:3A Timestamp : Dec 5 10:28:30.274 2025 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:B0:75:6B:49:89:8A:0D:B7:68:E9:A5: 1E:C1:11:A1:F6:04:F1:C3:05:EA:3D:23:1D:A7:24:81: 04:B8:90:AB:DA:02:20:6B:A1:83:3C:DF:C5:85:4E:26: D1:E2:B6:99:3D:8C:68:4B:01:70:02:12:48:58:E9:75: F1:69:B4:0C:3B:D8:A8 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 : Dec 5 10:28:30.282 2025 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:BA:4B:3E:9F:5C:37:44:82:4B:44:E3: 42:24:1E:ED:AF:43:CE:92:69:4A:28:68:E1:2A:A3:23: 5F:13:FE:82:5A:02:21:00:96:A8:A1:F3:2F:C3:97:75: 1E:03:6A:AE:C0:77:30:E3:CB:86:28:E4:62:00:AC:21: 5E:EE:05:6D:B0:EE:36:B2 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : D8:09:55:3B:94:4F:7A:FF:C8:16:19:6F:94:4F:85:AB: B0:F8:FC:5E:87:55:26:0F:15:D1:2E:72:BB:45:4B:14 Timestamp : Dec 5 10:28:30.232 2025 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:63:0A:AD:FF:85:42:B9:0B:53:66:AA:A7: 62:8F:BA:77:6F:58:F2:A7:99:9B:DE:1F:DD:B1:24:6A: 74:F5:C8:95:02:20:1E:DC:EC:DF:30:69:4F:3D:02:76: 38:E2:BD:69:47:71:3E:ED:71:01:2C:35:D0:98:63:88: 0A:14:38:9A:F1:F9
-----BEGIN CERTIFICATE-----
MIIG9TCCBV2gAwIBAgIQGpYItxdlAf7Xniauu+GkmzANBgkqhkiG9w0BAQsFADBg
MQswCQYDVQQGEwJHUjE3MDUGA1UECgwuSGVsbGVuaWMgQWNhZGVtaWMgYW5kIFJl
c2VhcmNoIEluc3RpdHV0aW9ucyBDQTEYMBYGA1UEAwwPR0VBTlQgVExTIFJTQSAx
MB4XDTI1MTIwNTEwMTgyOFoXDTI2MTIwNTEwMTgyOFowazELMAkGA1UEBhMCU0sx
EzARBgNVBAcMCkJyYXRpc2xhdmExNjA0BgNVBAoMLVNsb3ZlbnNrw6EgdGVjaG5p
Y2vDoSB1bml2ZXJ6aXRhIHYgQnJhdGlzbGF2ZTEPMA0GA1UEAwwGYnRzLnNrMIIB
IjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAyrv1fTM8Dfz2JGXIIwo6Taj1
2z/Daa8Vi6ebZz9BGd2MjgH+gjYJHtRYMIdCFFoY65xaL51fnZsk3GEzWdv7XNa9
gDPFWMF+7h6xhByItHTdCc7g++qQceAZwP9utp76aL3831voXqR20en9duKN/u3a
iXuO9Nwh+EINUHWltXoM3Ks5kuinKhJK4JN0dG9EBB3TsJM196q817DtimCOSi5Z
tyO/PHZMczDFmKDm+3GnzVboAdZp1cfGSHTK9duUcZ34BownMCpJV4o9iZM2BTlU
3QUv+0xjdkq2Klp0ApsAQxibRdgmkJeu/8hENMhX8jnw2yD//mIm7D0hFqyXaQID
AQABo4IDHjCCAxowDAYDVR0TAQH/BAIwADAfBgNVHSMEGDAWgBSGAXI/jKlw4jEG
UxbOAV9becg8OzBvBggrBgEFBQcBAQRjMGEwOAYIKwYBBQUHMAKGLGh0dHA6Ly9j
cnQuaGFyaWNhLmdyL0hBUklDQS1HRUFOVC1UTFMtUjEuY2VyMCUGCCsGAQUFBzAB
hhlodHRwOi8vb2NzcC10bHMuaGFyaWNhLmdyMDoGA1UdEQQzMDGCBmJ0cy5za4IK
d3d3LmJ0cy5za4ILbWFpbC5idHMuc2uCDndlYm1haWwuYnRzLnNrMC0GA1UdIAQm
MCQwCAYGZ4EMAQICMAgGBgQAj3oBBzAOBgwrBgEEAYHPEQEBAQIwHQYDVR0lBBYw
FAYIKwYBBQUHAwIGCCsGAQUFBwMBMD0GA1UdHwQ2MDQwMqAwoC6GLGh0dHA6Ly9j
cmwuaGFyaWNhLmdyL0hBUklDQS1HRUFOVC1UTFMtUjEuY3JsMB0GA1UdDgQWBBSr
E1W0+8mkjiRg34gX56pqu1NuJjAOBgNVHQ8BAf8EBAMCBaAwggF+BgorBgEEAdZ5
AgQCBIIBbgSCAWoBaAB2AK9niDtXsE7dj6bZfvYuqOuBCsdxYPAkXlXWDC/nhYc6
AAABmu4OXcIAAAQDAEcwRQIhALB1a0mJig23aOmlHsERofYE8cMF6j0jHackgQS4
kKvaAiBroYM838WFTibR4raZPYxoSwFwAhJIWOl18Wm0DDvYqAB3AJROQ4f67MHv
gfMZJCaoGGUBx9NfOAIBP3JnfVU3LhnYAAABmu4OXcoAAAQDAEgwRgIhALpLPp9c
N0SCS0TjQiQe7a9DzpJpSiho4SqjI18T/oJaAiEAlqih8y/Dl3UeA2quwHcw48uG
KORiAKwhXu4FbbDuNrIAdQDYCVU7lE96/8gWGW+UT4WrsPj8XodVJg8V0S5yu0VL
FAAAAZruDl2YAAAEAwBGMEQCIGMKrf+FQrkLU2aqp2KPundvWPKnmZveH92xJGp0
9ciVAiAe3OzfMGlPPQJ2OOK9aUdxPu1xASw10JhjiAoUOJrx+TANBgkqhkiG9w0B
AQsFAAOCAYEAFC626lwOvjKHmLevOmY6wDXyLzNY4pMoHD/It1JbyLt6G9UYE3qP
xKe0Mbk0JpCKVNckKgDstJGfbTljy2QGqLCw48qRNEE9QyYqa2JS6LWPGB5sm1HH
srL/kpJTqc9KvDR7yWYKfYePAEp9OD1A5B3kpz27/h/Lv4yWw7fDXnjoSNYv4nX1
8hkAVq4j4YL/cA8xeIyg4bstoDWigZKntsXRolJ52BCQ2fHnRF7mwsgROhADJf+N
+3KIh2A5ZjAepjhttsZDsITiKLTDT6mtcWFGdmshMH+qZv5102Ees1yOGpNE4p/2
iu36/4OfIdNRziI9MNz5/rGh+HO5vyB9bvChbqh2HkbuG3Z8Lg5R8ekNni+WYYai
ZLJ/P6X+9V+zdWDEqzQiFPAAmbG4KnS3PpZs4Mfn2UoFEk/h5D+pvHoNY2QBkfao
9tJSTByrD1ww/nuTEC7Zdam2/zo9CYInfF1BmT2YC7swTdODoYSSWKyLyI8c6hl3
nZkhHuo5OCpk
-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-09-23T18:15:48+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=GR O=Hellenic Academic and Research Institutions CA CN=GEANT TLS RSA 1
Issuer
C=GR O=Hellenic Academic and Research Institutions CA CN=HARICA TLS RSA Root CA 2021
Valid from
2025-01-03T11:15:00+00:00
Expires
2039-12-31T11:14:59+00:00
Days remaining
4846
Serial (hex)
14D57BF3692228219A5567FA91651B22
Signature
RSA-SHA256
Public key
RSA 3072

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

5B:67:8D:C4:40:95:A5:28:95:B6:3B:31:F2:72:27:F4:B3:6C:3E:34:74:91:BF:2B:FA:69:18:37:A5:FB:8C:79
Certificate extensions & PEM
basicConstraints
CA:TRUE, pathlen:0
authorityKeyIdentifier
0A:48:23:A6:60:A4:92:0A:33:EA:93:5B:C5:57:EA:25:4D:BD:12:EE
authorityInfoAccess
CA Issuers - URI:http://crt.harica.gr/HARICA-TLS-Root-2021-RSA.cer
certificatePolicies
Policy: X509v3 Any Policy
extendedKeyUsage
TLS Web Client Authentication, TLS Web Server Authentication
crlDistributionPoints
Full Name: URI:http://crl.harica.gr/HARICA-TLS-Root-2021-RSA.crl
subjectKeyIdentifier
86:01:72:3F:8C:A9:70:E2:31:06:53:16:CE:01:5F:5B:79:C8:3C:3B
keyUsage
Digital Signature, Certificate Sign, CRL Sign
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Chain certificate 2

Subject
C=GR O=Hellenic Academic and Research Institutions CA CN=HARICA TLS RSA Root CA 2021
Issuer
C=GR L=Athens O=Hellenic Academic and Research Institutions Cert. Authority CN=Hellenic Academic and Research Institutions RootCA 2015
Valid from
2021-09-02T07:41:55+00:00
Expires
2029-08-31T07:41:54+00:00
Days remaining
1072
Serial (hex)
2A6086D4D4DE45C95E4B98FBBF2FBF26
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

4A:CD:8D:C6:02:0A:54:5A:85:89:43:A5:53:B5:E0:F3:FC:5B:85:9A:EA:17:46:65:0D:69:CF:12:10:F9:56:D8
Certificate extensions & PEM
basicConstraints
CA:TRUE
authorityKeyIdentifier
71:15:67:C8:C8:C9:BD:75:5D:72:D0:38:18:6A:9D:F3:71:24:54:0B
authorityInfoAccess
CA Issuers - URI:http://repo.harica.gr/certs/HaricaRootCA2015.crt
certificatePolicies
Policy: X509v3 Any Policy
extendedKeyUsage
TLS Web Client Authentication, TLS Web Server Authentication
crlDistributionPoints
Full Name: URI:http://crl.harica.gr/HaricaRootCA2015.crl
subjectKeyIdentifier
0A:48:23:A6:60:A4:92:0A:33:EA:93:5B:C5:57:EA:25:4D:BD:12:EE
keyUsage
Digital Signature, Certificate Sign, CRL Sign
-----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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