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

netronik.pl · 155.133.33.133:443

Verified

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

Subject
CN=*.netronik.pl
Issuer
C=PL O=Asseco Data Systems S.A. CN=Certum DV TLS G2 R39 CA
Valid from
2026-01-23T11:02:41+00:00
Expires
2027-01-23T11:02:40+00:00
Days remaining
111
Serial (hex)
3D91A3F2537E5BF9FF34249114472D03
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:*.netronik.pl, DNS:netronik.pl

SHA-256 fingerprint

CB:34:3E:4C:15:5F:19:D6:DF:B7:E2:E3:67:2E:5F:F5:08:CB:2A:23:05:C1:C8:82:EB:25:49:18:91:2A:98:C1
Certificate extensions & PEM
basicConstraints
CA:FALSE
crlDistributionPoints
Full Name: URI:http://certumdvtlsg2r39ca.crl.certum.pl/certumdvtlsg2r39ca.crl
authorityInfoAccess
OCSP - URI:http://certumdvtlsg2r39ca.ocsp-certum.com CA Issuers - URI:http://certumdvtlsg2r39ca.repository.certum.pl/certumdvtlsg2r39ca.cer
authorityKeyIdentifier
33:A8:77:B7:01:38:6F:5F:1F:24:24:A2:1E:6C:14:E3:6E:22:03:DF
certificatePolicies
Policy: 2.23.140.1.2.1 Policy: 1.2.616.1.113527.2.101.1
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
keyUsage
Digital Signature, Key Encipherment
subjectAltName
DNS:*.netronik.pl, DNS:netronik.pl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 60:4C:9A:AF:7A:7F:77:5F:01:D4:06:FC:92:0D:C8:99: EB:0B:1C:7D:F8:C9:52:1B:FA:FA:17:77:3B:97:8B:C9 Timestamp : Jan 23 11:02:42.462 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:1F:F5:F9:30:4A:F3:11:37:D9:A4:E1:E2: 4A:B3:67:F1:49:2C:1F:ED:36:02:2D:17:BE:5E:43:78: 40:02:79:EE:02:20:66:C0:42:A0:03:BE:1B:9B:8E:0A: 5A:7E:29:64:1A:AF:08:76:30:A2:64:A7:34:34:37:AD: D7:DC:E9:AF:61:2D Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 59:6E:6C:33:86:94:B2:59:72:A2:56:C8:A0:E8:DD:90: 4A:76:E8:08:3D:DA:87:3B:01:08:38:28:14:3C:EE:59 Timestamp : Jan 23 11:02:42.633 2026 GMT Extensions: 00:00:05:00:00:14:2F:1D Signature : ecdsa-with-SHA256 30:44:02:20:1A:4A:C5:47:C6:74:98:D3:5C:14:20:20: C4:80:F7:B8:2E:6B:3F:42:D8:AC:C8:14:38:58:2F:C8: 2D:A9:68:52:02:20:16:EA:8F:21:C6:6B:88:D4:26:76: D2:BB:42:37:69:EF:BF:92:CF:DB:4F:FA:29:A7:BB:48: E8:FE:85:89:2C:8A Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1C:9F:68:2C:E9:FA:F0:45:69:50:F8:1B:96:8A:87:DD: DB:32:10:D8:4C:E6:C8:B2:E3:82:52:4A:C4:CF:59:9F Timestamp : Jan 23 11:02:42.653 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:29:09:B4:E6:6D:7E:34:B6:F6:EA:83:A9: D6:17:EC:D7:FC:A7:12:FD:1E:A5:76:84:E0:05:A3:D2: D0:0D:F1:2F:02:20:1F:59:65:2C:7B:C5:A5:B8:4A:DF: 11:50:B7:6C:5B:F9:53:F3:86:B9:26:56:97:D7:7B:06: D8:F6:47:82:EB:AC
-----BEGIN CERTIFICATE-----
MIIHFzCCBP+gAwIBAgIQPZGj8lN+W/n/NCSRFEctAzANBgkqhkiG9w0BAQsFADBS
MQswCQYDVQQGEwJQTDEhMB8GA1UECgwYQXNzZWNvIERhdGEgU3lzdGVtcyBTLkEu
MSAwHgYDVQQDDBdDZXJ0dW0gRFYgVExTIEcyIFIzOSBDQTAeFw0yNjAxMjMxMTAy
NDFaFw0yNzAxMjMxMTAyNDBaMBgxFjAUBgNVBAMMDSoubmV0cm9uaWsucGwwggEi
MA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQDFV8XweFSfadxt2dpCLa0OF60U
trAKP3FEUYVVWCvi91CGGWKMed4RICeC5DkcHSIxmUqVbP+/FEuVIUnyVxp8rW9d
cC1M9yaoQeCSLWlFSVJ4FgNPaB8CqBcQhhERrwRVcbTYJSVu43Xc6aRPJQnYoSyM
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WjnhCgF/L26r3kN1K2zWR0jdwU2j7oVjF6zAwi6OFuhAwKDWncxuONfXdiwgWmcH
uTXgWbiULlmTI8jF67nfP0dJ5JGLFx5KYAABl5H4lzVW5hk5hmwYcZ7xo3obAgMB
AAGjggMhMIIDHTAMBgNVHRMBAf8EAjAAME8GA1UdHwRIMEYwRKBCoECGPmh0dHA6
Ly9jZXJ0dW1kdnRsc2cycjM5Y2EuY3JsLmNlcnR1bS5wbC9jZXJ0dW1kdnRsc2cy
cjM5Y2EuY3JsMIGaBggrBgEFBQcBAQSBjTCBijA1BggrBgEFBQcwAYYpaHR0cDov
L2NlcnR1bWR2dGxzZzJyMzljYS5vY3NwLWNlcnR1bS5jb20wUQYIKwYBBQUHMAKG
RWh0dHA6Ly9jZXJ0dW1kdnRsc2cycjM5Y2EucmVwb3NpdG9yeS5jZXJ0dW0ucGwv
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JQQWMBQGCCsGAQUFBwMBBggrBgEFBQcDAjAOBgNVHQ8BAf8EBAMCBaAwJQYDVR0R
BB4wHIINKi5uZXRyb25pay5wbIILbmV0cm9uaWsucGwwggGDBgorBgEEAdZ5AgQC
BIIBcwSCAW8BbQB1AGBMmq96f3dfAdQG/JINyJnrCxx9+MlSG/r6F3c7l4vJAAAB
m+qFSh4AAAQDAEYwRAIgH/X5MErzETfZpOHiSrNn8UksH+02Ai0Xvl5DeEACee4C
IGbAQqADvhubjgpafilkGq8IdjCiZKc0NDet19zpr2EtAH0AWW5sM4aUsllyolbI
oOjdkEp26Ag92oc7AQg4KBQ87lkAAAGb6oVKyQAIAAAFAAAULx0EAwBGMEQCIBpK
xUfGdJjTXBQgIMSA97guaz9C2KzIFDhYL8gtqWhSAiAW6o8hxmuI1CZ20rtCN2nv
v5LP20/6Kae7SOj+hYksigB1AByfaCzp+vBFaVD4G5aKh93bMhDYTObIsuOCUkrE
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0tAN8S8CIB9ZZSx7xaW4St8RULdsW/lT84a5JlaX13sG2PZHguusMA0GCSqGSIb3
DQEBCwUAA4ICAQCTnELJYiyPPWMiRrMMXjWgyZJeIAZRNipgBfXu41KpDIeNC5Qs
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7tTfqbt0qGBhZMEef9uKoOnRP/GusP+YAomZYdc3zPbKjxtS2hiFSb4yN4jExyZd
ddFmGr22ojx0MtLO0HwmLaaKuYQ4w4of7v44SSCQ+WsMCXxce5zOWBO43jrMMsG5
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4hTKYJYfGFtj91gPC+du3IhOPiYEsA2JxuwrAdZaqoSBiCZA8obNI/SK73agzAGM
mncwxvLAzu5Qte34i81BzGk70XgbVr4IwV4phrSH+QJUfPzpAJ6tKdJqdoN7mKDO
ED8xFunLsBRPD9jz9hEK7Gfz8eScKV/tpBOMvAyJYe/2oMfzlU3T+ICJpYSdNu0D
TRRZ/a5YLJpXcfm8ItkM4VX3fHNk9TMp4E/ZBeqG91jAhxW7WBGJy8vjYmpIt/LD
GJJ+kPKIYnMzFgxDntNCi9Pyh28alPu//mmDuH5RSJgKH/YDTVWecCcMlg==
-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-10-03T18:40:12+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=PL O=Asseco Data Systems S.A. CN=Certum DV TLS G2 R39 CA
Issuer
C=PL O=Asseco Data Systems S.A. OU=Certum Certification Authority CN=Certum Trusted Root CA
Valid from
2024-06-18T07:41:22+00:00
Expires
2039-06-05T07:41:22+00:00
Days remaining
4627
Serial (hex)
A82DD9E5DCAFDF13205E70043E6B95A8
Signature
RSA-SHA512
Public key
RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

83:C0:A5:A7:68:44:C8:40:DF:AF:82:0F:FD:02:AD:F6:57:3A:26:82:3E:F6:AF:75:8A:33:84:A0:AC:04:40:83
Certificate extensions & PEM
authorityInfoAccess
CA Issuers - URI:http://subca.repository.certum.pl/ctrca.cer OCSP - URI:http://subca.ocsp-certum.com
authorityKeyIdentifier
8C:FB:1C:75:BC:02:D3:9F:4E:2E:48:D9:F9:60:54:AA:C4:B3:4F:FA
basicConstraints
CA:TRUE, pathlen:0
crlDistributionPoints
Full Name: URI:http://subca.crl.certum.pl/ctrca.crl
extendedKeyUsage
TLS Web Client Authentication, TLS Web Server Authentication
keyUsage
Certificate Sign, CRL Sign
certificatePolicies
Policy: X509v3 Any Policy
subjectKeyIdentifier
33:A8:77:B7:01:38:6F:5F:1F:24:24:A2:1E:6C:14:E3:6E:22:03:DF
-----BEGIN CERTIFICATE-----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H5o7DtoGiWXvcRKYpGtWt9czdUa1edSk5mTrwZGEXLAkX1ECiAq4GS5vEGjrEQ1u
x8mag2LDh7ZnXdcyzkKZKGsx7uExe3Nx5gWWZMXFrZ5v+uxynKogHUY2vdIMB3dn
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PtYwxP1nNpxwBgtIPoTk6wIDAQABo4IBRDCCAUAwcQYIKwYBBQUHAQEEZTBjMDcG
CCsGAQUFBzAChitodHRwOi8vc3ViY2EucmVwb3NpdG9yeS5jZXJ0dW0ucGwvY3Ry
Y2EuY2VyMCgGCCsGAQUFBzABhhxodHRwOi8vc3ViY2Eub2NzcC1jZXJ0dW0uY29t
MB8GA1UdIwQYMBaAFIz7HHW8AtOfTi5I2flgVKrEs0/6MBIGA1UdEwEB/wQIMAYB
Af8CAQAwNQYDVR0fBC4wLDAqoCigJoYkaHR0cDovL3N1YmNhLmNybC5jZXJ0dW0u
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HQ8BAf8EBAMCAQYwEQYDVR0gBAowCDAGBgRVHSAAMB0GA1UdDgQWBBQzqHe3AThv
Xx8kJKIebBTjbiID3zANBgkqhkiG9w0BAQ0FAAOCAgEACDQ1ggBelZZ/NYs1nFKW
HnDrA8Y4pv0lvxLzSAC4ejGavMXqPTXHA+DEh9kHNd8tVlo24+6YN96Gspb1kMXR
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K6PqlhYkeMOkx+XbmUuUgh29T0sPne7/V6PHnbEJIxUs40+iLCF0HrdqZypjvWQq
pSmHRHI3UWVERDeERca0uJ3I+a5ER9vUL9u5ilGG4afyx7QwzitBG+1rU3nRsHyZ
g6osILL/MWc0AbWJMyKzQ9Guj+uwq47h6BC9BsWF34pJeDC8EuN3HNxPlSWSII9l
Omwtipvq0EL1iocJhXdlsG+jIUVs/Sl/Um9JiZV+h/MoytnrPrWMIj+0zz6BdaPP
2sT6wcLzpnwYcE9FWSbQrzNpL283EOUkObjc8AIxICzPHGusF0IqsO+sj9XzvLTh
TjKfFlzx4NR8gbK7m8sXq6cgP4UAtyvDswebFIRQiuhjqOT9G7+56+4zC0RaEZx/
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8FpPkganuCwy++7umTkM7+Q=
-----END CERTIFICATE-----

Chain certificate 2

Subject
C=PL O=Asseco Data Systems S.A. OU=Certum Certification Authority CN=Certum Trusted Root CA
Issuer
C=PL O=Asseco Data Systems S.A. OU=Certum Certification Authority CN=Certum Trusted Root CA
Valid from
2018-03-16T12:10:13+00:00
Expires
2043-03-16T12:10:13+00:00
Days remaining
6007
Serial (hex)
1EBF5950B8C980374C06F7EB554FB5ED
Signature
RSA-SHA512
Public key
RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

FE:76:96:57:38:55:77:3E:37:A9:5E:7A:D4:D9:CC:96:C3:01:57:C1:5D:31:76:5B:A9:B1:57:04:E1:AE:78:FD
Certificate extensions & PEM
basicConstraints
CA:TRUE
subjectKeyIdentifier
8C:FB:1C:75:BC:02:D3:9F:4E:2E:48:D9:F9:60:54:AA:C4:B3:4F:FA
keyUsage
Certificate Sign, CRL Sign
-----BEGIN CERTIFICATE-----
MIIFwDCCA6igAwIBAgIQHr9ZULjJgDdMBvfrVU+17TANBgkqhkiG9w0BAQ0FADB6
MQswCQYDVQQGEwJQTDEhMB8GA1UEChMYQXNzZWNvIERhdGEgU3lzdGVtcyBTLkEu
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0ISVoDwUQwbKytu4QTbaakRnh6+v40URFWkIsr4WOZckbxJF0WddCajJFdr60qZf
E2Efv4WstK2tBZQIgx51F9NxO5NQI1mg7TyRVJ12AMXDuDjb
-----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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