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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

cas.cz · 147.231.163.240:443

Verified

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

Subject
C=CZ ST=Hlavní město Praha L=Praha 1 O=Středisko společných činností AV ČR, v. v. i. CN=avcr.cz
Issuer
C=GR O=Hellenic Academic and Research Institutions CA CN=GEANT TLS ECC 1
Valid from
2026-07-22T17:44:51+00:00
Expires
2027-02-06T17:44:50+00:00
Days remaining
131
Serial (hex)
67BE34E3B493DBB40FDDF2E9FB39EAB3
Signature
ecdsa-with-SHA384
Public key
EC 256 prime256v1

Subject alternative names (SAN)

DNS:avcr.cz, DNS:www.cas.cz, DNS:cas.cz, DNS:www.avcr.cz

SHA-256 fingerprint

3E:4A:AB:F2:D9:40:C5:A7:8A:40:CC:85:A6:18:4D:8F:5B:E9:B3:ED:58:9B:E0:E6:0D:01:7A:95:1A:40:8B:78
Certificate extensions & PEM
basicConstraints
CA:FALSE
authorityKeyIdentifier
E9:99:06:8D:17:1F:AB:FB:96:1A:5A:C8:5B:5E:5D:5E:EC:DA:9C:8F
authorityInfoAccess
CA Issuers - URI:http://crt.harica.gr/HARICA-GEANT-TLS-E1.cer
subjectAltName
DNS:avcr.cz, DNS:www.cas.cz, DNS:cas.cz, DNS:www.avcr.cz
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-E1.crl
subjectKeyIdentifier
C0:55:87:84:67:29:0D:59:E9:CC:DA:EB:03:A4:8F:06:20:2F:8D:E0
keyUsage
Digital Signature
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 60:4C:9A:AF:7A:7F:77:5F:01:D4:06:FC:92:0D:C8:99: EB:0B:1C:7D:F8:C9:52:1B:FA:FA:17:77:3B:97:8B:C9 Timestamp : Jul 22 17:54:54.008 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:9B:1C:C2:E4:86:AD:50:3C:41:31:B7: 43:F4:EE:33:4A:86:65:00:98:02:C5:62:17:D9:C4:D3: 80:1E:F8:13:4C:02:21:00:84:FE:82:D8:ED:30:BB:E9: EC:8E:CA:70:37:BA:32:13:CB:94:BD:F6:A0:CB:22:30: E9:F0:39:FA:93:FA:C1:E1 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 46:A2:39:67:C6:0D:B6:46:87:C6:6F:3D:F9:99:94:76: 93:A6:A6:11:20:84:57:D5:55:E7:E3:D0:A1:D9:B6:46 Timestamp : Jul 22 17:54:54.033 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:96:92:DC:25:AF:C1:F7:65:F7:7A:0F: B3:8B:95:B2:AB:1F:57:E6:6A:26:65:F0:92:7B:21:3A: 25:D7:47:4A:99:02:20:67:4E:93:AB:EA:45:A0:AF:0E: 43:E0:00:43:4C:31:1F:B0:52:5A:F0:09:F1:9C:66:B3: D2:A8:2D:81:DE:B5:81 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 44:C2:BD:0C:E9:14:0E:64:A5:C9:4A:01:93:0A:5A:A1: BB:35:97:0E:00:EE:11:16:89:68:2A:1C:44:D7:B5:66 Timestamp : Jul 22 17:54:53.978 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:37:2C:83:F0:A9:FE:B2:45:52:02:2B:8B: DF:86:E0:E7:25:76:B7:D9:76:19:6F:AC:6C:87:E7:79: 54:A8:10:66:02:21:00:F3:05:69:C4:8E:82:5B:C1:00: BE:C1:9B:A0:95:D2:17:73:DC:F3:3F:0A:FD:7C:A2:59: B6:BC:89:8B:4A:F6:32
-----BEGIN CERTIFICATE-----
MIIFATCCBIagAwIBAgIQZ74047ST27QP3fLp+znqszAKBggqhkjOPQQDAzBgMQsw
CQYDVQQGEwJHUjE3MDUGA1UECgwuSGVsbGVuaWMgQWNhZGVtaWMgYW5kIFJlc2Vh
cmNoIEluc3RpdHV0aW9ucyBDQTEYMBYGA1UEAwwPR0VBTlQgVExTIEVDQyAxMB4X
DTI2MDcyMjE3NDQ1MVoXDTI3MDIwNjE3NDQ1MFowgY4xCzAJBgNVBAYTAkNaMR0w
GwYDVQQIDBRIbGF2bsOtIG3Em3N0byBQcmFoYTEQMA4GA1UEBwwHUHJhaGEgMTE8
MDoGA1UECgwzU3TFmWVkaXNrbyBzcG9sZcSNbsO9Y2ggxI1pbm5vc3TDrSBBViDE
jFIsIHYuIHYuIGkuMRAwDgYDVQQDDAdhdmNyLmN6MFkwEwYHKoZIzj0CAQYIKoZI
zj0DAQcDQgAESlM5IExdxd/dK3l1d5hIwrAtW0XiXKqSBkFzq7KNt4fJM/HmKKL0
HcSj0M3sWD+0wqaLgWwV9ZWhOTdb9d9F7KOCAvEwggLtMAwGA1UdEwEB/wQCMAAw
HwYDVR0jBBgwFoAU6ZkGjRcfq/uWGlrIW15dXuzanI8wSAYIKwYBBQUHAQEEPDA6
MDgGCCsGAQUFBzAChixodHRwOi8vY3J0LmhhcmljYS5nci9IQVJJQ0EtR0VBTlQt
VExTLUUxLmNlcjAzBgNVHREELDAqggdhdmNyLmN6ggp3d3cuY2FzLmN6ggZjYXMu
Y3qCC3d3dy5hdmNyLmN6MC0GA1UdIAQmMCQwCAYGZ4EMAQICMAgGBgQAj3oBBzAO
BgwrBgEEAYHPEQEBAQIwHQYDVR0lBBYwFAYIKwYBBQUHAwIGCCsGAQUFBwMBMD0G
A1UdHwQ2MDQwMqAwoC6GLGh0dHA6Ly9jcmwuaGFyaWNhLmdyL0hBUklDQS1HRUFO
VC1UTFMtRTEuY3JsMB0GA1UdDgQWBBTAVYeEZykNWenM2usDpI8GIC+N4DAOBgNV
HQ8BAf8EBAMCB4AwggF/BgorBgEEAdZ5AgQCBIIBbwSCAWsBaQB3AGBMmq96f3df
AdQG/JINyJnrCxx9+MlSG/r6F3c7l4vJAAABn4r3WbgAAAQDAEgwRgIhAJscwuSG
rVA8QTG3Q/TuM0qGZQCYAsViF9nE04Ae+BNMAiEAhP6C2O0wu+nsjspwN7oyE8uU
vfagyyIw6fA5+pP6weEAdgBGojlnxg22RofGbz35mZR2k6amESCEV9VV5+PQodm2
RgAAAZ+K91nRAAAEAwBHMEUCIQCWktwlr8H3Zfd6D7OLlbKrH1fmaiZl8JJ7ITol
10dKmQIgZ06Tq+pFoK8OQ+AAQ0wxH7BSWvAJ8Zxms9KoLYHetYEAdgBEwr0M6RQO
ZKXJSgGTClqhuzWXDgDuERaJaCocRNe1ZgAAAZ+K91maAAAEAwBHMEUCIDcsg/Cp
/rJFUgIri9+G4OcldrfZdhlvrGyH53lUqBBmAiEA8wVpxI6CW8EAvsGboJXSF3Pc
8z8K/XyiWba8iYtK9jIwCgYIKoZIzj0EAwMDaQAwZgIxAMFNEQOZGB7Q3Vj0hIkE
JpSvKme5+Kz4lZnP5PSbuLB/5N7D232MvpQOyWN6pX8AxgIxAMXOYMw/98+EqnOy
rhr1xTiFqjRAr1/ZI/gyaHHm9+V7Z6YrpFl5/MAklSfcyTdTEQ==
-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-09-28T16:01:57+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=GR O=Hellenic Academic and Research Institutions CA CN=GEANT TLS ECC 1
Issuer
C=GR O=Hellenic Academic and Research Institutions CA CN=HARICA TLS ECC Root CA 2021
Valid from
2025-01-03T11:14:21+00:00
Expires
2039-12-31T11:14:20+00:00
Days remaining
4841
Serial (hex)
42FDDCE1261607E1A5E6935A400161DD
Signature
ecdsa-with-SHA384
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

6C:DF:0B:A1:71:1E:85:6D:22:8B:A0:0C:A0:4C:5C:1C:3D:79:94:4C:03:7B:71:3B:15:5A:4E:E4:B4:7E:C5:3C
Certificate extensions & PEM
basicConstraints
CA:TRUE, pathlen:0
authorityKeyIdentifier
C9:1B:53:81:12:FE:04:D5:16:D1:AA:BC:9A:6F:B7:A0:95:19:6E:CA
authorityInfoAccess
CA Issuers - URI:http://crt.harica.gr/HARICA-TLS-Root-2021-ECC.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-ECC.crl
subjectKeyIdentifier
E9:99:06:8D:17:1F:AB:FB:96:1A:5A:C8:5B:5E:5D:5E:EC:DA:9C:8F
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 ECC Root CA 2021
Issuer
C=GR L=Athens O=Hellenic Academic and Research Institutions Cert. Authority CN=Hellenic Academic and Research Institutions ECC RootCA 2015
Valid from
2021-09-02T07:44:37+00:00
Expires
2029-08-31T07:44:36+00:00
Days remaining
1067
Serial (hex)
716027C8857A73542DEF516C1C2EEB0F
Signature
ecdsa-with-SHA384
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

50:E2:7F:90:EB:6A:F4:95:B0:E6:EE:B6:55:CC:89:44:4C:27:D3:C9:5B:68:23:FA:02:AB:DC:95:F1:63:6A:E1
Certificate extensions & PEM
basicConstraints
CA:TRUE
authorityKeyIdentifier
B4:22:0B:82:99:24:01:0E:9C:BB:E4:0E:FD:BF:FB:97:20:93:99:2A
authorityInfoAccess
CA Issuers - URI:http://repo.harica.gr/certs/HaricaECCRootCA2015.crt
certificatePolicies
Policy: X509v3 Any Policy
extendedKeyUsage
TLS Web Client Authentication, TLS Web Server Authentication
crlDistributionPoints
Full Name: URI:http://crl.harica.gr/HaricaECCRootCA2015.crl
subjectKeyIdentifier
C9:1B:53:81:12:FE:04:D5:16:D1:AA:BC:9A:6F:B7:A0:95:19:6E:CA
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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