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

ns2.bartanet.cz · 192.162.96.1:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. Peer certificate subjectAltName did not match expected name `ns2.bartanet.cz'

Certificate verification failed

Subject
CN=bad1.bartanet.cz
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-09-29T16:56:08+00:00
Expires
2026-12-28T16:56:07+00:00
Days remaining
52
Serial (hex)
05B775B63923F5DD108C6119DD082035A315
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:bad1.bartanet.cz, DNS:dhcp1.bartanet.cz, DNS:gw.bartanet.cz, DNS:nep1.bartanet.cz, DNS:speed.bartanet.cz, DNS:speedtest.bartanet.cz, DNS:stop1.bartanet.cz, DNS:test.bartanet.cz

SHA-256 fingerprint

67:DF:8B:8E:1D:4C:1F:28:37:3B:9B:EE:08:E6:B7:5B:17:CC:DC:0B:2B:76:E2:54:E1:5C:02:90:4F:FC:88:FF
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
D7:4A:B2:6D:5F:A0:8B:1C:AA:D8:9E:7E:91:4E:42:BE:DB:6D:5A:85
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:bad1.bartanet.cz, DNS:dhcp1.bartanet.cz, DNS:gw.bartanet.cz, DNS:nep1.bartanet.cz, DNS:speed.bartanet.cz, DNS:speedtest.bartanet.cz, DNS:stop1.bartanet.cz, DNS:test.bartanet.cz
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/22.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 29 17:54:38.422 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:5F:FD:4F:50:D2:EF:19:D1:0E:EE:A3:20: 82:0D:8C:76:06:92:22:1E:66:F1:29:58:28:C5:3D:8C: 8C:15:57:28:02:21:00:94:DA:C4:5F:DC:07:27:A6:61: FD:3C:13:24:B8:14:1B:58:F4:C5:BB:90:49:22:3D:46: 64:84:79:B5:F1:A9:7D 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 29 17:54:38.653 2026 GMT Extensions: 00:00:05:00:18:1C:78:64 Signature : ecdsa-with-SHA256 30:45:02:21:00:D4:E7:4F:9B:02:49:5C:06:23:4D:CD: C4:F0:10:F3:27:67:E7:BD:18:89:EC:9D:CB:44:09:DB: 00:E5:09:7A:E9:02:20:45:DA:60:8C:2D:42:DF:CC:C7: 0B:BB:5C:E5:70:9D:49:04:23:07:A1:62:B5:B1:9B:FB: D2:0E:7B:9F:60:08:25
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-11-06T16:14:16+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
666
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-----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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
2127
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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