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

ffmuc.freifunk.net · 5.1.66.255:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. Peer certificate subjectAltName did not match expected name `ffmuc.freifunk.net'
The certificate expires within 30 days.

Certificate verification failed

Subject
Issuer
C=US O=Let's Encrypt CN=YE2
Valid from
2026-11-13T12:20:30+00:00
Expires
2026-11-20T04:20:29+00:00
Days remaining
6
Serial (hex)
05475C440F5EF8C40B3890199C312242AEA6
Signature
ecdsa-with-SHA384
Public key
EC 256 prime256v1

Subject alternative names (SAN)

DNS:anycast.ffmuc.net, DNS:anycast01.ffmuc.net, DNS:anycast02.ffmuc.net, DNS:dns.ffmuc.net, DNS:doh.ffmuc.net, DNS:doq.ffmuc.net, DNS:dot.ffmuc.net, IP Address:185.150.99.255, IP Address:2001:678:E68:F000:0:0:0:0, IP Address:2001:678:E68:FF00:0:0:0:1, IP Address:2001:678:ED0:F000:0:0:0:0, IP Address:5.1.66.1, IP Address:5.1.66.255

SHA-256 fingerprint

95:3C:F6:71:DA:6D:4B:B2:51:AC:35:5D:54:59:F7:69:71:1F:38:13:EF:DE:6F:AF:85:97:2C:36:EA:F8:C9:DE
Certificate extensions & PEM
keyUsage
Digital Signature
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
authorityKeyIdentifier
B9:59:F2:8E:CF:22:F0:86:D3:37:48:FF:76:14:18:BA:82:D8:55:87
authorityInfoAccess
CA Issuers - URI:http://ye2.i.lencr.org/
subjectAltName
DNS:anycast.ffmuc.net, DNS:anycast01.ffmuc.net, DNS:anycast02.ffmuc.net, DNS:dns.ffmuc.net, DNS:doh.ffmuc.net, DNS:doq.ffmuc.net, DNS:dot.ffmuc.net, IP Address:185.150.99.255, IP Address:2001:678:E68:F000:0:0:0:0, IP Address:2001:678:E68:FF00:0:0:0:1, IP Address:2001:678:ED0:F000:0:0:0:0, IP Address:5.1.66.1, IP Address:5.1.66.255
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://ye2.c.lencr.org/39.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 : Nov 13 13:19:00.370 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:26:AE:5C:0E:51:42:C7:7C:AF:81:B3:09: DF:29:91:07:B6:25:5F:AD:CC:A2:BE:8D:68:61:89:72: 76:F0:7F:64:02:20:28:DC:F3:F0:4C:BB:12:27:A5:2B: F5:65:DF:24:42:AD:CD:27:55:CF:2E:7B:16:CA:A2:9B: 1D:D4:06:AB:4F:E0 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : A8:26:CB:E3:0A:C6:35:12:46:53:3F:E0:65:F1:4F:19: D9:6E:19:08:13:C4:1D:D9:6D:79:00:B3:12:3C:55:27 Timestamp : Nov 13 13:19:03.022 2026 GMT Extensions: 00:00:05:00:3E:B0:C3:F7 Signature : ecdsa-with-SHA256 30:44:02:20:11:19:AA:F8:FA:AA:E8:8B:2A:7F:84:18: D8:A2:02:60:52:68:32:1A:15:ED:BB:50:FE:40:7C:53: 2C:B1:2B:83:02:20:07:F2:87:DB:40:27:BC:B8:8E:DA: 5A:4E:1D:F1:3A:FB:08:B0:8B:1F:8A:89:D4:CA:7C:7C: 83:EC:01:96:46:D4
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-11-14T00:57:26+00:00

Server-presented chain · 3 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YE2
Issuer
C=US O=ISRG CN=Root YE
Valid from
2025-09-03T00:00:00+00:00
Expires
2028-09-02T23:59:59+00:00
Days remaining
658
Serial (hex)
4DF3B15DD6C0784C507CD37B58E6F115
Signature
ecdsa-with-SHA384
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

97:65:8D:E8:C6:8D:FA:98:AC:E1:E5:02:8A:63:D5:4A:1A:AE:91:1B:3E:21:47:10:76:C6:85:0C:D0:8C:BA:B4
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
B9:59:F2:8E:CF:22:F0:86:D3:37:48:FF:76:14:18:BA:82:D8:55:87
authorityKeyIdentifier
A3:C8:26:5A:8E:A1:4C:D0:35:63:FC:9B:23:C8:3A:AE:56:F3:4F:56
authorityInfoAccess
CA Issuers - URI:http://ye.i.lencr.org/
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://ye.c.lencr.org/ 
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Chain certificate 2

Subject
C=US O=ISRG CN=Root YE
Issuer
C=US O=Internet Security Research Group CN=ISRG Root X2
Valid from
2026-05-13T00:00:00+00:00
Expires
2032-09-02T23:59:59+00:00
Days remaining
2119
Serial (hex)
872165FC34B6E5FBA8ADD5B3705FB53A
Signature
ecdsa-with-SHA384
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

0F:C0:90:1C:CA:2B:AE:9E:9F:DB:B0:2D:50:D0:2F:10:94:F7:B3:66:72:08:69:91:B9:E8:97:62:6D:C4:85:F0
Certificate extensions & PEM
keyUsage
Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE
subjectKeyIdentifier
A3:C8:26:5A:8E:A1:4C:D0:35:63:FC:9B:23:C8:3A:AE:56:F3:4F:56
authorityKeyIdentifier
7C:42:96:AE:DE:4B:48:3B:FA:92:F8:9E:8C:CF:6D:8B:A9:72:37:95
authorityInfoAccess
CA Issuers - URI:http://x2.i.lencr.org/
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://x2.c.lencr.org/ 
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Chain certificate 3

Subject
C=US O=Internet Security Research Group CN=ISRG Root X2
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
2119
Serial (hex)
6C8F1DC727C7117F7BAF853AC980F9CD
Signature
RSA-SHA256
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

EE:5F:7A:BD:69:81:BB:02:55:63:2C:D8:F4:92:83:45:1B:4B:18:84:4D:12:04:0B:44:EE:00:F0:7B:8F:E2:C6
Certificate extensions & PEM
keyUsage
Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
basicConstraints
CA:TRUE
subjectKeyIdentifier
7C:42:96:AE:DE:4B:48:3B:FA:92:F8:9E:8C:CF:6D:8B:A9:72:37:95
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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