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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

seppmail.ch · 116.202.28.251:443

Verified

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

Subject
CN=seppmail.ch
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-09-10T03:25:31+00:00
Expires
2026-12-09T03:25:30+00:00
Days remaining
69
Serial (hex)
06BBFADA79260D817FBBD80772A6256EE363
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:seppmail.ch, DNS:www.seppmail.ch

SHA-256 fingerprint

64:C8:1E:68:7D:98:8C:65:85:14:9E:AA:82:D4:13:64:BD:09:75:A6:52:84:2A:0D:B4:31:1B:9E:86:C5:18:99
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
94:CC:F0:6C:7F:1F:16:B8:6C:33:8E:5F:81:11:58:55:86:3E:99:FB
authorityKeyIdentifier
1F:2F:35:BE:46:14:82:CD:40:B1:AE:79:2C:55:78:FA:F7:D4:68:FB
authorityInfoAccess
CA Issuers - URI:http://yr1.i.lencr.org/
subjectAltName
DNS:seppmail.ch, DNS:www.seppmail.ch
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/100.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 26:E3:64:6E:58:69:21:23:BC:34:3F:47:24:35:9B:37: 92:CD:24:5A:88:D8:15:D3:93:33:FD:99:18:AB:47:23 Timestamp : Sep 10 04:23:59.910 2026 GMT Extensions: 00:00:05:00:3F:84:7E:CB Signature : ecdsa-with-SHA256 30:46:02:21:00:B6:82:B6:B7:EB:EA:41:8F:6A:D7:AF: C0:DD:62:E3:58:CA:DC:C2:DC:8E:3D:5B:C6:3D:5D:F4: 03:A7:51:80:2F:02:21:00:B4:1E:CB:9D:7C:C9:FD:E9: 53:40:F7:10:9A:AF:0C:74:E4:CA:12:33:3B:55:2A:49: 1A:A0:4A:C3:6E:68:D7:6E Signed Certificate Timestamp: Version : v1 (0x0) Log ID : D7:6D:7D:10:D1:A7:F5:77:C2:C7:E9:5F:D7:00:BF:F9: 82:C9:33:5A:65:E1:D0:B3:01:73:17:C0:C8:C5:69:77 Timestamp : Sep 10 04:24:03.940 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:29:07:4B:C2:C6:22:B1:B2:D4:D5:7A:D4: C8:57:04:4C:44:0F:E9:C1:95:8F:97:19:D1:1F:3E:16: 1C:71:77:43:02:21:00:F8:1E:8B:E0:82:2E:D1:69:1F: 9C:50:9A:6F:11:9E:49:2E:F4:68:28:2A:41:CE:E4:A0: E1:81:EB:5B:7D:9E:EF
-----BEGIN CERTIFICATE-----
MIIGAzCCBOugAwIBAgISBrv62nkmDYF/u9gHcqYlbuNjMA0GCSqGSIb3DQEBCwUA
MDMxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MQwwCgYDVQQD
EwNZUjEwHhcNMjYwOTEwMDMyNTMxWhcNMjYxMjA5MDMyNTMwWjAWMRQwEgYDVQQD
EwtzZXBwbWFpbC5jaDCCAiIwDQYJKoZIhvcNAQEBBQADggIPADCCAgoCggIBAL8V
DmlDM94ZCbXq8a0ZOTbsDrX1NStWIHi7HTbW95a7sqvRLCN9TqGKldhQexVz4+42
+vszhMSMKqHw/vGY26FMNV3xCea2+trl+PbuGzkV77uOpI+pXWRVF4PHHLqrHCfr
BS15Q0VutYvLDjt7b/pdVJb0o80eupCIkYH4wRkHx7OeCWqlTW4B6/Sq34aFyiN2
k28ztGBbuzCwIeU7OYgXkZbf34hRUs+0NulYX2UW9bQyFSzxB0TLbQnCUpwUN9HP
iwcCWOEVEt4pO4sW7pwTrh17WzVtc4nBDMWbsvg2JDqMaTPvbSndq+yridrZ+ji2
feUMk4GPrHRdQDkbcL0ustsW6CETkdM0Qxrka7jCtzS/KiC4Z2EVuYqeW+aDDdc4
xOKcK1NUwK80a72lx+4xPfdqHL7rMv19lOYLKOmm93+YSj8zEFBHBB1LHcW3zeOF
9rrIatjugj3Vwm02PfvQmQWEg3lImlKmBGuo4TB6fMLGBjc+KE8CX7FUeMzZF+ZZ
75xkYpxPkofPDZsPi0gjEHV9N56gkscq8/kPUCqZAeMtY/r6WA9TQL1JewayHtvH
fwcP7nJL1MCeu8ohLhgCJnf4JHRHjdqHiwZPMOZmrtk/wKwOCCg/ADb7fvRccaza
SgBujXU5rXbCN6jYuwYRdZlTPuf7xiU4tPngxCJPAgMBAAGjggIsMIICKDAOBgNV
HQ8BAf8EBAMCBaAwEwYDVR0lBAwwCgYIKwYBBQUHAwEwDAYDVR0TAQH/BAIwADAd
BgNVHQ4EFgQUlMzwbH8fFrhsM45fgRFYVYY+mfswHwYDVR0jBBgwFoAUHy81vkYU
gs1Asa55LFV4+vfUaPswMwYIKwYBBQUHAQEEJzAlMCMGCCsGAQUFBzAChhdodHRw
Oi8veXIxLmkubGVuY3Iub3JnLzAnBgNVHREEIDAeggtzZXBwbWFpbC5jaIIPd3d3
LnNlcHBtYWlsLmNoMBMGA1UdIAQMMAowCAYGZ4EMAQIBMC8GA1UdHwQoMCYwJKAi
oCCGHmh0dHA6Ly95cjEuYy5sZW5jci5vcmcvMTAwLmNybDCCAQ0GCisGAQQB1nkC
BAIEgf4EgfsA+QB/ACbjZG5YaSEjvDQ/RyQ1mzeSzSRaiNgV05Mz/ZkYq0cjAAAB
oImO6qYACAAABQA/hH7LBAMASDBGAiEAtoK2t+vqQY9q16/A3WLjWMrcwtyOPVvG
PV30A6dRgC8CIQC0HsudfMn96VNA9xCarwx05MoSMztVKkkaoErDbmjXbgB2ANdt
fRDRp/V3wsfpX9cAv/mCyTNaZeHQswFzF8DIxWl3AAABoImO+mQAAAQDAEcwRQIg
KQdLwsYisbLU1XrUyFcETEQP6cGVj5cZ0R8+Fhxxd0MCIQD4Hovggi7RaR+cUJpv
EZ5JLvRoKCpBzuSg4YHrW32e7zANBgkqhkiG9w0BAQsFAAOCAQEAelsIBnIpRLgw
xJERrUy7h7czpkue1NurKSLyySEo7ZHS1QAXAwg9ozi62qWrboYSBCLxGaxxZNxM
OPFOpsA3hrfPQBIQCKRMkhil8dK+Lo5chLnd02O1UI5nQXZjNJlkPZ14y5ss4rdz
7/6BvHwad2sZU1D8Bp62OA6Il1DWptXT/To55+w8GuRZtrji7nZcnk8zprPQEEe1
+CfhZ4FqNiAMWcsrTL9qVTkxykXpUrDXNDOMobiS+MlXmcNE6NRWjpWSW8KGLCL3
s3b/Cv/XHmShc/Nn++Cg+9GBwinoc3+G2xxzfOHztQ7JhRFwurztNNYWWGCAtIes
t9N+pvw4hA==
-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-09-30T07:19:52+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YR1
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
703
Serial (hex)
A20253F15F2691C05DC1CE13B9BCCA4E
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

13:94:96:34:D9:9C:D6:FD:6A:A8:0B:C0:34:FE:FA:CC:EB:19:69:FE:EF:98:65:86:71:3E:CD:BB:05:75:8D:3F
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
1F:2F:35:BE:46:14:82:CD:40:B1:AE:79:2C:55:78:FA:F7:D4:68:FB
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
2164
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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