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

mail.ispu.ru · 85.142.148.171:443

Verified

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

Subject
CN=mail.ispu.ru
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-11-04T11:34:20+00:00
Expires
2027-02-02T11:34:19+00:00
Days remaining
83
Serial (hex)
06D144A61D129B024208654E8F3A564A7A23
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:autoconfig.ispu.ru, DNS:autodiscover.ispu.ru, DNS:mail.ispu.ru

SHA-256 fingerprint

6A:79:1F:0C:F1:AD:BF:73:6A:09:2A:64:82:78:E0:5F:90:6F:76:36:8E:51:A9:65:18:A6:47:74:C0:54:8A:C3
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
2E:CB:95:D8:D3:05:B5:A6:DE:84:1A:EA:28:E8:E2:5D:45:E2:36:1E
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:autoconfig.ispu.ru, DNS:autodiscover.ispu.ru, DNS:mail.ispu.ru
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/36.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 8E:CA:47:0B:AC:DE:6A:F3:A2:06:B0:A4:7A:84:B7:46: FE:1F:C6:BF:95:3E:25:E6:9B:4E:E4:02:48:F3:C6:E8 Timestamp : Nov 4 12:32:51.148 2026 GMT Extensions: 00:00:05:00:38:16:70:B0 Signature : ecdsa-with-SHA256 30:45:02:21:00:A1:18:60:2B:D1:FF:58:86:C8:75:5B: B8:B6:97:D8:8E:F0:FB:31:A9:77:54:17:E7:D7:20:90: D2:B0:09:11:32:02:20:4C:F4:26:10:E4:70:87:8B:66: A8:2E:11:E7:7D:02:44:58:30:D9:51:68:2C:BE:64:11: 21:02:5E:BE:52:6E:62 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 60:4C:9A:AF:7A:7F:77:5F:01:D4:06:FC:92:0D:C8:99: EB:0B:1C:7D:F8:C9:52:1B:FA:FA:17:77:3B:97:8B:C9 Timestamp : Nov 4 12:32:51.165 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:CB:07:5D:C8:A5:D8:F3:6B:99:54:52: D1:85:E6:77:8D:EB:AA:40:28:F2:EE:C5:26:BA:53:33: F1:88:FC:54:36:02:20:11:25:07:A2:A9:4F:26:3D:57: 87:2B:07:74:9B:01:D5:73:F1:A5:BB:80:6B:D9:A3:73: 70:54:81:F2:31:C6:4E
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-11-11T00:36:08+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
661
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
2122
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

Registration / WHOIS →DNS records →