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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

lisek.pl · 37.131.166.15:443

Verified

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

Subject
CN=lisek.pl
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-09-16T23:13:19+00:00
Expires
2026-12-15T23:13:18+00:00
Days remaining
49
Serial (hex)
06FA691BF301217B31B4DDDC793BC1481A98
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:lisek.pl, DNS:www.lisek.pl

SHA-256 fingerprint

B4:79:E8:E1:52:CD:16:CE:7D:B5:8D:AB:D2:0A:FB:FD:19:62:77:D4:E8:75:96:70:2A:69:2A:D7:1E:DB:17:1E
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
78:C2:16:42:8B:08:39:7B:76:71:0F:8F:93:3E:BD:1A:BA:92:8D:CE
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:lisek.pl, DNS:www.lisek.pl
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/25.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : C2:31:7E:57:45:19:A3:45:EE:7F:38:DE:B2:90:41:EB: C7:C2:21:5A:22:BF:7F:D5:B5:AD:76:9A:D9:0E:52:CD Timestamp : Sep 17 00:11:49.439 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:09:2F:17:9E:C0:12:D1:F0:9D:87:07:C8: 4A:DB:B7:A1:73:E5:CE:F4:0A:B8:53:64:4A:09:5A:CB: BC:7F:52:4E:02:21:00:FC:EB:C8:BE:0B:FE:14:B0:EE: 37:D7:CD:11:02:FD:0B:9B:21:7F:5F:2A:76:89:ED:AB: CC:DB:88:A8:55:6F:5F Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 46:AF:86:3D:3B:3E:E5:9F:A5:77:DE:A8:24:5D:36:B0: D9:ED:22:A2:23:F4:61:77:41:22:94:52:EE:95:50:5F Timestamp : Sep 17 00:11:49.661 2026 GMT Extensions: 00:00:05:00:30:4C:35:3F Signature : ecdsa-with-SHA256 30:44:02:20:47:C5:50:89:78:6A:D3:3F:F5:5B:AC:34: ED:88:57:63:14:BD:59:AE:20:99:52:8C:6F:F3:5C:87: EF:E0:96:8D:02:20:77:46:58:8C:70:B8:5D:73:A3:D0: 7B:89:CA:C3:63:23:B1:A9:04:D0:C6:3F:B5:DD:F2:87: 41:F0:8D:CE:35:5A
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-10-27T22:36:14+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
676
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
2137
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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