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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

mail.bit-net.kr · 211.174.100.4:443

Verified

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

Subject
CN=mail.bit-net.kr
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-09-01T11:40:38+00:00
Expires
2026-11-30T11:40:37+00:00
Days remaining
67
Serial (hex)
055799C6293B2DC91AE13592CABB876A3069
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:mail.bit-net.kr

SHA-256 fingerprint

4D:AB:11:39:AB:A5:0D:C5:07:DA:7A:77:22:14:0E:81:F5:74:19:B2:74:04:9D:FF:CF:46:23:3F:58:E8:D0:61
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
CE:9C:B3:BA:A8:E4:E3:46:D6:4D:47:AC:1C:2A:EE:32:1B:24:A5:E9
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:mail.bit-net.kr
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/106.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 1 12:39:08.802 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:73:34:FF:27:BC:3C:3B:0D:FC:07:12:25: DB:A5:E6:84:5F:96:3A:76:88:39:A3:6F:7B:B5:36:55: FF:C6:60:80:02:21:00:A9:FB:DF:02:BB:5F:60:7C:69: F6:69:D0:05:7D:5C:B2:42:DD:0E:C3:F3:EE:B6:AA:77: 7E:51:44:0A:59:07:F3 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 : Sep 1 12:39:09.215 2026 GMT Extensions: 00:00:05:00:2A:06:AF:F0 Signature : ecdsa-with-SHA256 30:45:02:21:00:F3:2E:FB:66:08:60:4E:EE:20:E5:38: A6:E4:87:0B:F6:1A:DC:67:DB:35:99:67:3A:21:E9:56: 7C:7F:8A:AF:2D:02:20:5B:91:50:F8:2D:6A:70:47:68: CD:38:2A:CC:8A:99:62:13:5A:7F:CE:CF:DB:B5:B8:89: CB:01:EB:13:21:1B:C2
-----BEGIN CERTIFICATE-----
MIIF+TCCBOGgAwIBAgISBVeZxik7Lcka4TWSyruHajBpMA0GCSqGSIb3DQEBCwUA
MDMxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MQwwCgYDVQQD
EwNZUjIwHhcNMjYwOTAxMTE0MDM4WhcNMjYxMTMwMTE0MDM3WjAaMRgwFgYDVQQD
Ew9tYWlsLmJpdC1uZXQua3IwggIiMA0GCSqGSIb3DQEBAQUAA4ICDwAwggIKAoIC
AQDXnkclmyNhO/ubrr8OrSephOcdWCmtGhX3oAvC5lUcOVEMkj91dwbPYEPGKyif
ksrDTGFs5uak6ZcjMMGXwSrPMUEsV37qL0rpFvlR+tKZl+djdvs3H7NV7eueIcHk
ToVnqidwwcirKh8ytMuGX8Pns+Ca3FtTQ/JAX9X8N+gwgx6u6zDSwVviueoMVLmh
wcnKewKOfgbdTKFtK4bmo5ytMnvZ4RLGGPF4PjLAwu+3GoXPwSIqFaWnpixA406p
JtXLsXv2ZIsgpj0vg6UEZSU/PW8nb07no5W0rSY40q0IIEtjUuT1Mht6pJAK1Ej7
Igr68TEOqdIdyf3Gk7U6lpdkr+01JiHXPgUCJoQWVNSjUpEg4S/Dg0KXFzuiGroa
KMsLcnPJRG4fni2AvlsJQb8qRI8Cs6afxwVT8ipi4V2R+wHOwJ4OOUFPl9kF0PNO
IHa6Ut3V9+iOepy6kR+loWAtdx7t85Qqh5V7CN57i97hvK6thXgfax8xmroSvcj/
XkKbpaplU54HcL5UDQTQEGlgXTEIfI2rr6HGdbdCsS29IS9m4KRQ/6pjC6EUTVo+
Ah0NOODvlTEiDgfv80m9PDvDSKpXGDcIEqcnfTF9dPuHPxAY5zKrR5tsyr2wppOK
RM8YvKG0iQFV2il1CoVaURv/w9RXCxcXuOzLrAhTCattdQIDAQABo4ICHjCCAhow
DgYDVR0PAQH/BAQDAgWgMBMGA1UdJQQMMAoGCCsGAQUFBwMBMAwGA1UdEwEB/wQC
MAAwHQYDVR0OBBYEFM6cs7qo5ONG1k1HrBwq7jIbJKXpMB8GA1UdIwQYMBaAFEAV
LSZ57TIgnt+ach3WMh+BDIEMMDMGCCsGAQUFBwEBBCcwJTAjBggrBgEFBQcwAoYX
aHR0cDovL3lyMi5pLmxlbmNyLm9yZy8wGgYDVR0RBBMwEYIPbWFpbC5iaXQtbmV0
LmtyMBMGA1UdIAQMMAowCAYGZ4EMAQIBMC8GA1UdHwQoMCYwJKAioCCGHmh0dHA6
Ly95cjIuYy5sZW5jci5vcmcvMTA2LmNybDCCAQwGCisGAQQB1nkCBAIEgf0EgfoA
+AB2AMIxfldFGaNF7n843rKQQevHwiFaIr9/1bWtdprZDlLNAAABoFz7AQIAAAQD
AEcwRQIgczT/J7w8Ow38BxIl26XmhF+WOnaIOaNve7U2Vf/GYIACIQCp+98Cu19g
fGn2adAFfVyyQt0Ow/Putqp3flFEClkH8wB+AKgmy+MKxjUSRlM/4GXxTxnZbhkI
E8Qd2W15ALMSPFUnAAABoFz7Ap8ACAAABQAqBq/wBAMARzBFAiEA8y77ZghgTu4g
5Tim5IcL9hrcZ9s1mWc6IelWfH+Kry0CIFuRUPgtanBHaM04KsyKmWITWn/Oz9u1
uInLAesTIRvCMA0GCSqGSIb3DQEBCwUAA4IBAQA25cgLNnTsn7Y8gMdDUezuJl9R
lHjGI9hOLPp8tHi+gJxk8BlqjZoZYM7PGdFeFi6aZDspjiHLCFuftLrSorZT6R6h
R33lUFlWvy4WTsraWq9VyMVmOJ7WGwG98cIM+iZfgxE93riMGbeQVs82SuZr6Ppn
rP6N6X0luXFxD9pRm3NBwJyYoJ2dE9ebOnuH8AVaEAcFIgsEfRBb1gPpgwcyCdes
43teCc3+y8+QW5Dk6Ch0maUUMT395dlVhsdg4beHfV6zVC5h8jHgwFw6Pqfmm195
PxQxW+0ZWY5ie3spbh3iut+hm8aYlOC1w5v4ovHBAhUc3mc/mRGyP6LERakj
-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-09-23T19:06:14+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
710
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
2171
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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