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

onet.sk · 37.9.175.197:443

Verified

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

Subject
CN=onet.sk
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-08-21T07:40:09+00:00
Expires
2026-11-19T07:40:08+00:00
Days remaining
31
Serial (hex)
0586F3AA7EC6D0E6E5D9F7B6B63C15A0E0DD
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:*.onet.sk, DNS:onet.sk

SHA-256 fingerprint

DB:46:F1:45:2C:59:F0:58:03:A6:17:0E:C3:50:AF:6A:98:25:9A:D4:80:A1:DA:F9:37:45:5A:31:EA:90:EB:14
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
91:A0:8C:28:3F:7C:F6:50:CC:96:7C:CE:99:A5:C3:0D:89:89:FC:32
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:*.onet.sk, DNS:onet.sk
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/94.crl
ct_precert_scts
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 : Aug 21 08:38:40.277 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:CC:15:D8:B5:7E:0E:3F:78:E9:67:A1: 5C:8E:52:CA:6C:03:B3:8F:70:F5:4E:E2:5C:C6:DF:97: 81:69:78:27:50:02:21:00:EA:22:F2:3C:8F:38:F6:10: 98:E9:08:D2:3C:95:77:EF:EC:2A:F1:99:14:85:3E:A3: A9:25:D2:C4:ED:67:7B:3D Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1A:8B:9D:6B:0F:FE:BF:81:B4:79:39:C6:D2:31:0A:86: D6:D1:02:D4:F0:46:E2:18:2C:9D:E3:5F:5E:26:25:EF Timestamp : Aug 21 08:38:40.363 2026 GMT Extensions: 00:00:05:00:36:DB:26:72 Signature : ecdsa-with-SHA256 30:46:02:21:00:F0:7C:30:53:C3:AD:7A:A6:06:B4:91: CE:A1:75:89:F1:E7:DA:6E:E5:0E:6F:F6:3A:34:44:BC: 93:0C:B1:B6:F9:02:21:00:9B:BE:C3:21:58:DB:62:68: 07:5F:5D:24:7E:A0:06:A0:71:45:FA:B0:75:28:80:37: EB:61:A3:4D:A1:18:41:CA
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-10-19T01:55:15+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
684
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
2145
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

Registration / WHOIS →DNS records →