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

TLSv1.2

ezisp.nl · 91.213.13.57:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. SSL operation failed with code 1. OpenSSL Error messages: error:0A000086:SSL routines::certificate verify failed
The certificate has expired.

Certificate verification failed

Subject
CN=kuhnen.nu
Issuer
C=US O=Let's Encrypt CN=R13
Valid from
2025-11-03T11:57:18+00:00
Expires
2026-02-01T11:57:17+00:00
Days remaining
-234
Serial (hex)
062458AEF5AE90787A74DE634AE9061AA8B8
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:kuhnen.nu, DNS:webmail.kuhnen.nu, DNS:www.kuhnen.nu

SHA-256 fingerprint

48:EE:3C:C8:8A:42:06:49:9F:58:91:D3:1C:0F:C8:CB:0E:9F:2F:41:C9:F8:EF:40:73:71:A5:4F:64:E4:33:53
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
BA:83:9C:66:9E:A7:DF:56:93:3B:6E:90:08:58:D9:74:B1:A9:57:6D
authorityKeyIdentifier
E7:AB:9F:0F:2C:33:A0:53:D3:5E:4F:78:C8:B2:84:0E:3B:D6:92:33
authorityInfoAccess
CA Issuers - URI:http://r13.i.lencr.org/
subjectAltName
DNS:kuhnen.nu, DNS:webmail.kuhnen.nu, DNS:www.kuhnen.nu
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://r13.c.lencr.org/57.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : CB:38:F7:15:89:7C:84:A1:44:5F:5B:C1:DD:FB:C9:6E: F2:9A:59:CD:47:0A:69:05:85:B0:CB:14:C3:14:58:E7 Timestamp : Nov 3 12:55:48.924 2025 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:7E:FF:BB:CB:2F:C1:FD:95:C9:1F:54:00: 51:C5:0E:89:22:2C:55:12:1A:4E:C5:05:F1:94:B8:D5: 04:61:97:FD:02:21:00:DC:51:C7:59:5C:DE:FF:C3:82: 43:6F:C2:48:05:BA:8B:83:A5:BD:52:B9:AA:F6:BD:1D: 42:9E:1D:C2:06:4C:C0 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 49:9C:9B:69:DE:1D:7C:EC:FC:36:DE:CD:87:64:A6:B8: 5B:AF:0A:87:80:19:D1:55:52:FB:E9:EB:29:DD:F8:C3 Timestamp : Nov 3 12:55:48.913 2025 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:9D:B9:70:7E:67:53:0E:30:8B:D8:E3: B5:F2:14:4F:8B:B2:75:DC:6E:2C:AF:9D:EC:B3:C7:59: C1:7A:64:96:E1:02:21:00:EC:E0:1B:69:D7:C1:82:EE: 94:39:86:F2:EB:55:66:45:44:10:D8:4C:86:DA:77:11: 89:C6:74:0C:EE:81:CB:56
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: ECDHE-RSA-AES128-GCM-SHA256 · Checked 2026-09-23T10:04:12+00:00

Server-presented chain · 1 additional certificate

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=R13
Issuer
C=US O=Internet Security Research Group CN=ISRG Root X1
Valid from
2024-03-13T00:00:00+00:00
Expires
2027-03-12T23:59:59+00:00
Days remaining
170
Serial (hex)
5A00F212D8D4B480F3924157EA298305
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

D3:B1:28:21:6A:84:3F:8E:F1:32:15:01:F5:DF:52:A5:DF:52:93:9E:E2:C1:92:97:71:2C:D3:DE:4D:41:93:54
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Client Authentication, TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
E7:AB:9F:0F:2C:33:A0:53:D3:5E:4F:78:C8:B2:84:0E:3B:D6:92:33
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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