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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

nfx.cz · 81.201.48.120:443

Verified

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

Subject
CN=nfx.cz
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-09-28T21:05:34+00:00
Expires
2026-12-27T21:05:33+00:00
Days remaining
77
Serial (hex)
061E3A4E63D5CC6E9F302B01FFBB5BFA268D
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:gaia.nfx.cz, DNS:nfx.cz, DNS:portal.nfx.cz, DNS:wiki.nfx.cz, DNS:www.nfx.cz

SHA-256 fingerprint

1D:7A:A0:14:AA:7C:F4:27:68:CF:72:37:24:20:2A:FF:FF:3D:97:45:CB:F2:E3:F5:D9:C5:DD:37:5C:44:6F:C6
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
81:C0:0F:26:A5:4A:28:4B:C4:BC:B8:83:DA:A8:89:38:30:D6:5B:4A
authorityKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
authorityInfoAccess
CA Issuers - URI:http://yr2.i.lencr.org/
subjectAltName
DNS:gaia.nfx.cz, DNS:nfx.cz, DNS:portal.nfx.cz, DNS:wiki.nfx.cz, DNS:www.nfx.cz
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/14.crl
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 : Sep 28 22:04:04.471 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:E9:EF:97:C0:80:90:CE:DF:55:0B:DD: AE:BC:12:EB:16:DD:07:AF:14:E5:B8:E7:80:28:04:7D: 95:57:F3:F2:88:02:20:6F:6C:61:05:7E:B1:A2:56:D9: DC:A5:80:83:CD:9C:3C:B5:AE:11:76:D2:FB:75:6A:12: 9E:DA:BF:71:A7:9F:FB Signed Certificate Timestamp: Version : v1 (0x0) Log ID : A2:81:00:18:73:4E:17:6E:1D:47:E0:95:40:F3:81:BA: 54:66:97:CD:63:A8:43:50:71:6E:B8:09:4E:DA:F1:0D Timestamp : Sep 28 22:04:04.653 2026 GMT Extensions: 00:00:05:00:17:71:B7:E3 Signature : ecdsa-with-SHA256 30:45:02:21:00:9E:9C:05:0A:45:F9:D6:EC:48:4C:3D: 4E:76:AA:DA:CA:3A:CC:BE:A6:22:F2:CE:62:04:5F:85: E8:FE:B8:0B:4E:02:20:5B:AD:2D:A7:44:00:18:D0:ED: 3D:10:E2:77:73:19:CB:90:9C:6E:EF:17:CE:3A:E2:ED: 17:E7:DD:B9:58:30:4F
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-10-11T04:28:29+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YR2
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
692
Serial (hex)
4EBD24947E24D394802D84A52FD5B319
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

23:8B:85:A0:09:9C:65:B9:70:47:7D:57:24:F1:A1:D4:75:CE:50:58:CF:FE:4E:FA:87:33:89:9B:DB:86:3C:47
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
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-----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==
-----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
2153
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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