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

sak.ch · 82.199.136.133:443

Verified

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

Subject
CN=www.sak.ch
Issuer
C=US O=Let's Encrypt CN=YE1
Valid from
2026-09-22T10:45:07+00:00
Expires
2026-12-21T10:45:06+00:00
Days remaining
89
Serial (hex)
06AEF2F12438DEC4AB90B95653888472C2B7
Signature
ecdsa-with-SHA384
Public key
EC 384 secp384r1

Subject alternative names (SAN)

DNS:aktionen.saknet.ch, DNS:anleitungen.saknet.ch, DNS:energiemission.ch, DNS:glasfaser.saknet.ch, DNS:glasklarprint.saknet.ch, DNS:kundencenter.sak.ch, DNS:kundenzentrum.saknet.ch, DNS:linthwind.ch, DNS:sak-energiemission.ch, DNS:sak.ch, DNS:sakenergiemission.ch, DNS:sakforum.ch, DNS:saknet.ch, DNS:sakpedia.ch, DNS:saksmart.ch, DNS:stoerung.sak.ch, DNS:www.energiemission.ch, DNS:www.linthwind.ch, DNS:www.sak-energiemission.ch, DNS:www.sak.ch, DNS:www.sakenergiemission.ch, DNS:www.sakforum.ch, DNS:www.saknet.ch, DNS:www.sakpedia.ch, DNS:www.saksmart.ch

SHA-256 fingerprint

F1:E1:C0:5E:1F:C8:76:08:53:18:9A:8A:65:76:FB:83:58:28:BD:DF:B2:7E:74:E5:84:5F:DD:AB:8C:08:69:17
Certificate extensions & PEM
keyUsage
Digital Signature
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
13:23:3B:7C:7F:7E:97:98:60:49:6E:22:5B:53:C6:43:56:71:87:61
authorityKeyIdentifier
BB:20:CA:47:0B:FE:D7:E5:9C:F9:8F:09:2A:A3:8C:37:45:B1:BC:D8
authorityInfoAccess
CA Issuers - URI:http://ye1.i.lencr.org/
subjectAltName
DNS:aktionen.saknet.ch, DNS:anleitungen.saknet.ch, DNS:energiemission.ch, DNS:glasfaser.saknet.ch, DNS:glasklarprint.saknet.ch, DNS:kundencenter.sak.ch, DNS:kundenzentrum.saknet.ch, DNS:linthwind.ch, DNS:sak-energiemission.ch, DNS:sak.ch, DNS:sakenergiemission.ch, DNS:sakforum.ch, DNS:saknet.ch, DNS:sakpedia.ch, DNS:saksmart.ch, DNS:stoerung.sak.ch, DNS:www.energiemission.ch, DNS:www.linthwind.ch, DNS:www.sak-energiemission.ch, DNS:www.sak.ch, DNS:www.sakenergiemission.ch, DNS:www.sakforum.ch, DNS:www.saknet.ch, DNS:www.sakpedia.ch, DNS:www.saksmart.ch
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://ye1.c.lencr.org/56.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 22 11:43:37.927 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:46:B1:FE:91:5E:9C:13:09:F0:DA:2E:4C: F8:BE:A8:44:6D:30:9E:51:99:43:5F:8C:E9:12:5C:D9: B6:53:E4:80:02:20:38:DF:88:42:50:37:D5:DA:13:B5: BB:2C:A4:36:6A:F2:7B:68:21:24:C6:02:8F:E6:62:08: C0:AF:85:71:A2:F0 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : A2:81:00:18:73:4E:17:6E:1D:47:E0:95:40:F3:81:BA: 54:66:97:CD:63:A8:43:50:71:6E:B8:09:4E:DA:F1:0D Timestamp : Sep 22 11:43:38.654 2026 GMT Extensions: 00:00:05:00:12:61:66:39 Signature : ecdsa-with-SHA256 30:46:02:21:00:97:D3:01:A1:2F:6D:63:FA:89:69:2D: D4:F9:71:B6:9A:79:BD:1B:7E:21:7C:36:A0:E8:63:10: 4E:92:F3:B6:12:02:21:00:BC:35:C0:38:CF:E8:B6:F9: 73:B9:73:4B:D1:51:BA:00:0C:A2:9B:B8:C0:4A:75:B5: 34:56:23:78:EB:E3:6E:03
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-09-22T12:12:31+00:00

Server-presented chain · 3 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YE1
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
711
Serial (hex)
5DDD70DD31F801C85C186A7A04B80AFE
Signature
ecdsa-with-SHA384
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

A2:37:2D:06:43:1E:97:16:36:5E:EE:D4:7E:C0:20:35:14:97:D1:82:FC:C0:38:E4:57:E5:81:68:A0:3C:AC:07
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
BB:20:CA:47:0B:FE:D7:E5:9C:F9:8F:09:2A:A3:8C:37:45:B1:BC:D8
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
2172
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
2172
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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