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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.io · 162.55.214.61:443

Verified

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

Subject
CN=seppmail.io
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-08-20T07:14:08+00:00
Expires
2026-11-18T07:14:07+00:00
Days remaining
48
Serial (hex)
05595173737652690023A26641402A312942
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:seppmail.io

SHA-256 fingerprint

02:E1:A5:3E:6E:E4:0B:E5:B9:F2:D6:40:C4:9E:50:71:FE:43:A0:C7:5D:78:B4:55:03:2A:D3:F9:63:FB:3D:87
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
58:13:59:A4:4E:80:00:B6:9A:DD:0C:EB:E4:C9:B7:EC:50:BB:A6:25
authorityKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
authorityInfoAccess
CA Issuers - URI:http://yr2.i.lencr.org/
subjectAltName
DNS:seppmail.io
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/67.crl
ct_precert_scts
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 : Aug 20 08:12:39.211 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:4D:A3:C3:D0:BA:0B:2F:19:4E:32:71:EF: 7A:B1:B6:E1:42:5E:E3:A3:31:2A:E2:B3:90:23:47:5B: 61:3C:78:90:02:20:6B:E6:1E:2B:59:16:3F:A1:05:31: 87:AE:E5:86:0C:A4:C8:26:EA:5F:63:22:3F:91:00:51: F4:F3:DA:E8:42:99 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1A:8B:9D:6B:0F:FE:BF:81:B4:79:39:C6:D2:31:0A:86: D6:D1:02:D4:F0:46:E2:18:2C:9D:E3:5F:5E:26:25:EF Timestamp : Aug 20 08:12:39.363 2026 GMT Extensions: 00:00:05:00:36:6C:5F:85 Signature : ecdsa-with-SHA256 30:45:02:21:00:AF:2D:D9:BD:23:D0:59:D5:4F:B3:88: 41:B4:F5:D1:54:E9:0F:B5:70:8F:1C:9C:8D:E6:B9:F9: 5C:BB:B2:FB:4A:02:20:36:F9:1A:B8:A1:5A:4F:AB:62: 46:0D:07:E6:95:AA:52:34:EF:53:24:EF:5B:AD:92:AC: 1F:6E:30:33:F0:A1:F4
-----BEGIN CERTIFICATE-----
MIIF7zCCBNegAwIBAgISBVlRc3N2UmkAI6JmQUAqMSlCMA0GCSqGSIb3DQEBCwUA
MDMxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MQwwCgYDVQQD
EwNZUjIwHhcNMjYwODIwMDcxNDA4WhcNMjYxMTE4MDcxNDA3WjAWMRQwEgYDVQQD
EwtzZXBwbWFpbC5pbzCCAiIwDQYJKoZIhvcNAQEBBQADggIPADCCAgoCggIBALgh
RwuX/qSlnMl9NkEK7W+J/MllqmYZxO9AhF8oM3Ae9mUz4EFVmuIcvDyQo/Vwd594
2wsTKUv69sQ/5vE9cgjSDw6LKHNWbPdzrkWpOPJt4bGQdlXDsLN4/UHVB664JeSx
+x8JmPuiNuUKovuevWBbYriX14y9DMZc+igetkwikVmZ3q7XuAqgzUZKb90ohyK+
B/jwMb+zIzbnlOF7tWK+twULJDxlF+sCiQg8PjBKUaowgRxXazng72heJlyM4h6s
xbGVEX3eSL3/FRyarzy3CBTZxzTHtdfurXMfVCI9aoE29x1IjKjPi8SkoOcudz8s
0AV0Iejn+qNstyLdZ2dBm+rOtXRKz95yT8WCG6+ZTjNUeJ1w8YZsm6Fm//JpftGz
WjvI5qGm4635Y5F34231L4gPeg8SRSGcuym/NuoE6y81thvps8Ug3Fh0lgCw4L3l
G+P4cm0Ly7eiztE8VUf9fvJXk15L9MIaF7qo4/fbH3Q7GzQRdtwUG+Am3GUY3MfI
uTjeN6jo24XqyA+ZTfLeDi0SRKphaA6fgpgQJDbIzya+mM9kB9xIKI8GF5sTwLTV
wZiInx5xfA/iFdXBWX0RyQ+tJmQhmPk0Ed+jqDZRUXGz4Z8ZNbbNfR5dnpJti/MU
f8iaGRz/TuMHTkrat5uB5gEfo+vvFIXNFcpiTSSfAgMBAAGjggIYMIICFDAOBgNV
HQ8BAf8EBAMCBaAwEwYDVR0lBAwwCgYIKwYBBQUHAwEwDAYDVR0TAQH/BAIwADAd
BgNVHQ4EFgQUWBNZpE6AALaa3Qzr5Mm37FC7piUwHwYDVR0jBBgwFoAUQBUtJnnt
MiCe35pyHdYyH4EMgQwwMwYIKwYBBQUHAQEEJzAlMCMGCCsGAQUFBzAChhdodHRw
Oi8veXIyLmkubGVuY3Iub3JnLzAWBgNVHREEDzANggtzZXBwbWFpbC5pbzATBgNV
HSAEDDAKMAgGBmeBDAECATAuBgNVHR8EJzAlMCOgIaAfhh1odHRwOi8veXIyLmMu
bGVuY3Iub3JnLzY3LmNybDCCAQsGCisGAQQB1nkCBAIEgfwEgfkA9wB1ANdtfRDR
p/V3wsfpX9cAv/mCyTNaZeHQswFzF8DIxWl3AAABoB46tasAAAQDAEYwRAIgTaPD
0LoLLxlOMnHverG24UJe46MxKuKzkCNHW2E8eJACIGvmHitZFj+hBTGHruWGDKTI
JupfYyI/kQBR9PPa6EKZAH4AGoudaw/+v4G0eTnG0jEKhtbRAtTwRuIYLJ3jX14m
Je8AAAGgHjq2QwAIAAAFADZsX4UEAwBHMEUCIQCvLdm9I9BZ1U+ziEG09dFU6Q+1
cI8cnI3muflcu7L7SgIgNvkauKFaT6tiRg0H5pWqUjTvUyTvW62SrB9uMDPwofQw
DQYJKoZIhvcNAQELBQADggEBAF52yv290pJn7INHWtAa2pTYQEK94iq3MTQpYxDZ
ZIHfheBca1OFK+wRsfojC0LMj+79QW2II+FJNt3My0Ma7iAmscjvOKjjcz0Eh0zN
MIVxKRswuoj2SSQCKiFAbelTKYOiFQ/0OCdLnBqnoCh6yCQh9ZGrYsleYzAJFjD9
Xx9yc8Hq5H+5mi2yXIEjWSZg5YP6i25z9VeEXUfLM8EBR5gJps4ue1oswRuiUmq1
oeApByuNSGcbYDdmz4f0KD9drfiGOnZTpZ3vkbUh67+crp5hTktCs/unU0z/QWx9
uHnIrU8d5DNVRJyYkILGIDiMVFSf9IIXJ7NRhvfIqd3ES0I=
-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-09-30T10:06:44+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YR2
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)
4EBD24947E24D394802D84A52FD5B319
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

23:8B:85:A0:09:9C:65:B9:70:47:7D:57:24:F1:A1:D4:75:CE:50:58:CF:FE:4E:FA:87:33:89:9B:DB:86:3C:47
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
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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