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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

viridium.cz · 91.225.84.10:443

Verified

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

Subject
CN=viridium.cz
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-10-07T00:08:42+00:00
Expires
2027-01-05T00:08:41+00:00
Days remaining
58
Serial (hex)
06F2041AAC3529F736B3C7932435E04F3051
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:viridium.cz, DNS:www.viridium.cz

SHA-256 fingerprint

D6:04:14:05:5C:1F:10:3B:F4:0D:40:CE:6D:21:3F:06:90:DE:4D:BA:B1:EB:DA:89:BF:D5:A2:13:79:60:68:35
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
1C:EE:3E:D9:3E:7E:35:D2:08:80:CB:62:A0:3F:57:3C:23:59:A1:14
authorityKeyIdentifier
1F:2F:35:BE:46:14:82:CD:40:B1:AE:79:2C:55:78:FA:F7:D4:68:FB
authorityInfoAccess
CA Issuers - URI:http://yr1.i.lencr.org/
subjectAltName
DNS:viridium.cz, DNS:www.viridium.cz
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/82.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 00:1A:5D:1A:1C:2D:93:75:B6:48:55:78:F8:2F:71:A1: AE:6E:EF:39:7D:29:7C:8A:E3:15:7B:CA:DE:E1:A0:1E Timestamp : Oct 7 01:07:12.162 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:36:EC:26:3C:A4:7B:66:24:90:F9:BA:9A: 76:91:C7:E3:3D:DF:F9:BF:27:FC:AB:77:3A:62:08:F0: 4D:E1:AD:5C:02:21:00:9E:93:24:39:DF:75:54:48:D6: E0:E3:46:4C:55:1C:12:84:B2:65:54:53:00:7C:C4:15: D4:C5:4B:96:A0:B1:52 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1A:8B:9D:6B:8D:D7:91:D1:CD:05:49:ED:B6:03:55:D6: 06:B6:4F:AD:30:DB:71:FE:78:8F:0F:C7:C8:FB:C4:B1 Timestamp : Oct 7 01:07:13.579 2026 GMT Extensions: 00:00:05:00:06:0C:45:45 Signature : ecdsa-with-SHA256 30:46:02:21:00:B2:59:99:4A:B9:65:0B:DB:E3:36:F3: 62:43:A9:63:46:C2:39:E2:74:AC:89:25:5D:87:F5:33: 8B:47:7D:E1:91:02:21:00:A6:AE:0F:A8:66:E1:C9:94: A9:63:DE:EB:20:62:40:B0:91:66:C4:A1:E8:7F:26:0C: 5D:10:D0:65:B8:65:75:49
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-11-07T03:12:01+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YR1
Issuer
C=US O=ISRG CN=Root YR
Valid from
2025-09-03T00:00:00+00:00
Expires
2028-09-02T23:59:59+00:00
Days remaining
665
Serial (hex)
A20253F15F2691C05DC1CE13B9BCCA4E
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

13:94:96:34:D9:9C:D6:FD:6A:A8:0B:C0:34:FE:FA:CC:EB:19:69:FE:EF:98:65:86:71:3E:CD:BB:05:75:8D:3F
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
1F:2F:35:BE:46:14:82:CD:40:B1:AE:79:2C:55:78:FA:F7:D4:68:FB
authorityKeyIdentifier
DE:E7:5B:60:D0:22:6D:40:28:7D:3F:0D:01:FE:A4:B5:52:B4:51:94
authorityInfoAccess
CA Issuers - URI:http://yr.i.lencr.org/
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr.c.lencr.org/ 
-----BEGIN CERTIFICATE-----
MIIE2zCCAsOgAwIBAgIRAKICU/FfJpHAXcHOE7m8yk4wDQYJKoZIhvcNAQELBQAw
LjELMAkGA1UEBhMCVVMxDTALBgNVBAoTBElTUkcxEDAOBgNVBAMTB1Jvb3QgWVIw
HhcNMjUwOTAzMDAwMDAwWhcNMjgwOTAyMjM1OTU5WjAzMQswCQYDVQQGEwJVUzEW
MBQGA1UEChMNTGV0J3MgRW5jcnlwdDEMMAoGA1UEAxMDWVIxMIIBIjANBgkqhkiG
9w0BAQEFAAOCAQ8AMIIBCgKCAQEAoVi8X2xCYgMXvJxNPKp/oF13UMgmPABB07VC
LNDtoXmt9luEZNJSBV10VyT1Pz6LD8Zq1d2gc43WNl1AdRrj4sEnazbOiz0nPpmG
Bp2hui49oZtDIY6wdKeZAi5BbNU20CH6RSBBMLSQ9cXrH8dxdv4PAJ45ssGML68U
SE3BsjC2a6cAN9L5CgXVIQi5tfNiTPoFZZ3S0OlXqLmmtdV95udWAb5b6e/F49Di
CsH0Y00Ag72BVIb1hzynmKe+X0mERBTtsb3BwmpV9ipeBjMLoR/D9cHxHQCWoi5l
TmXwY015J5rGelz1nZjJuxc2kioaX29XJBnhMkP531rSdG5uMwIDAQABo4HuMIHr
MA4GA1UdDwEB/wQEAwIBhjATBgNVHSUEDDAKBggrBgEFBQcDATASBgNVHRMBAf8E
CDAGAQH/AgEAMB0GA1UdDgQWBBQfLzW+RhSCzUCxrnksVXj699Ro+zAfBgNVHSME
GDAWgBTe51tg0CJtQCh9Pw0B/qS1UrRRlDAyBggrBgEFBQcBAQQmMCQwIgYIKwYB
BQUHMAKGFmh0dHA6Ly95ci5pLmxlbmNyLm9yZy8wEwYDVR0gBAwwCjAIBgZngQwB
AgEwJwYDVR0fBCAwHjAcoBqgGIYWaHR0cDovL3lyLmMubGVuY3Iub3JnLzANBgkq
hkiG9w0BAQsFAAOCAgEA0+zvMq3kHig1ddTmmm+RibTr9/RpX7k4buanMMRqbV/y
IvP82zAHN3mvaw+cASuVsdpd0ikjhr4hnhJQLQOzOp2ccKrsdGOAgo0vddeISFAq
EWEV4lmUM3vFF796up+bSgmJ1u6RupDCMxDgF8M3eLvGuj6L0lu3zkQ0KuQLnKxL
tB0oQqn1Idg5CuuGpMvQzk29Pa3D/qHurc0EIM9SxukQuJqq63lxsYyRQFU8yMBO
hq1w5LbfaWNRrz1uklOfI/pYkAb2E2MTZrAMQkBIE2S8Jt1F8gRc96o/xOsrgvSk
a84AisX6xq1lz1Z7jGvrnXc4TMcjxZTjiTaihcYI1JIXZiLtEMSCa5l3cu8YWd6z
dLRQlqRdclVjuQfNHawRJ6GWlkK0QJosivTKwdBw3KxEtzGo8yMHERbsy57gP1UX
HOMcmZYQC0gtyR3SxfenIM/MxC3Ia2Ypab/kQ/CTnlIn2KQ5JUC6NYrGCbhFN9bp
5lKJStEwCUnLpntcrXk5XVDCNv/5RyWpRThkGOV7GetKkQ0qAY8hCzWK6oqnAhDZ
cjlYVdWfqOw3DIOX6EDNBgAqHarRVxyF9QZdOaXSyPJ0ueD2BYJEBgaCGQ8rAaU/
Qc123V5LTXDZW4CcsPBDyhy4v+c8hClAyw/IkJlfBqxB9D+/wvIMHgECZ4ptP6o=
-----END CERTIFICATE-----

Chain certificate 2

Subject
C=US O=ISRG CN=Root YR
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
2126
Serial (hex)
F24B6D17F9D9AD7CB1C9FEA78782699F
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

07:26:39:D0:B1:40:D5:BF:FA:E1:6A:D9:C3:F6:CC:60:86:04:06:21:F5:1E:E6:1A:6D:46:A8:91:5C:07:CF:76
Certificate extensions & PEM
keyUsage
Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE
subjectKeyIdentifier
DE:E7:5B:60:D0:22:6D:40:28:7D:3F:0D:01:FE:A4:B5:52:B4:51:94
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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