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

ns2.alsondns.net · 69.16.232.188:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. Peer certificate subjectAltName did not match expected name `ns2.alsondns.net'

Certificate verification failed

Subject
CN=coursesinvite.com
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-10-06T06:13:12+00:00
Expires
2027-01-04T06:13:11+00:00
Days remaining
58
Serial (hex)
054325CAEB962AAFCB4DB9F914EF2B8D5962
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:*.coursesinvite.com, DNS:coursesinvite.com

SHA-256 fingerprint

29:F1:02:D6:77:93:C4:1D:8D:8B:D4:E3:A5:3C:FA:67:D8:BF:D5:DE:63:C4:71:8A:FF:71:D0:2C:7E:A4:4C:E0
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
9F:21:68:C6:40:00:27:47:8D:FA:28:56:67:4C:6A:5E:9A:97:F2:CE
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:*.coursesinvite.com, DNS:coursesinvite.com
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/99.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 46:A2:39:67:C6:0D:B6:46:87:C6:6F:3D:F9:99:94:76: 93:A6:A6:11:20:84:57:D5:55:E7:E3:D0:A1:D9:B6:46 Timestamp : Oct 6 07:11:42.649 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:9A:EF:BF:7E:E3:8B:1C:13:F6:1F:7A: AC:8D:95:D6:4C:1C:C9:6F:BE:15:90:1C:9C:D5:3E:9D: 76:F0:D9:96:BA:02:20:7E:19:0C:AE:41:30:2D:36:A5: 50:18:ED:99:75:98:E4:AF:78:6A:49:C9:59:A4:A6:58: 39:CB:2D:8C:92:9D:63 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 : Oct 6 07:11:43.654 2026 GMT Extensions: 00:00:05:00:1D:85:AB:67 Signature : ecdsa-with-SHA256 30:45:02:21:00:B9:EB:45:B4:2A:0E:DA:77:2E:C9:FF: 06:B9:D0:C4:80:C4:AD:E8:08:92:A1:75:BE:B8:A1:3A: CD:0C:1C:52:C5:02:20:13:B1:88:BB:DD:4E:DD:FD:01: 93:07:4D:4F:BC:8D:51:9C:27:E6:9A:4A:BF:30:74:A0: BD:EE:AB:9C:47:2F:7B
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-11-06T16:14:22+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
666
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
2127
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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