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

bklynlibrary.org · 104.18.21.164:443

Verified

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

Subject
CN=bklynlibrary.org
Issuer
C=US O=Google Trust Services CN=WE1
Valid from
2026-08-15T11:05:40+00:00
Expires
2026-11-13T12:05:23+00:00
Days remaining
46
Serial (hex)
8509B2C132646A020E27D69C84D1BF32
Signature
ecdsa-with-SHA256
Public key
EC 256 prime256v1

Subject alternative names (SAN)

DNS:bklynlibrary.org, DNS:*.bklynlibrary.org

SHA-256 fingerprint

B8:3A:67:32:AB:D1:39:91:A0:2F:47:22:0B:57:C2:49:48:22:3E:47:4B:8E:96:45:81:0B:CF:8D:D2:79:53:17
Certificate extensions & PEM
keyUsage
Digital Signature
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
54:6A:78:C2:F3:8A:23:85:AB:97:6D:74:7C:46:9D:D9:27:3A:DD:47
authorityKeyIdentifier
90:77:92:35:67:C4:FF:A8:CC:A9:E6:7B:D9:80:79:7B:CC:93:F9:38
authorityInfoAccess
CA Issuers - URI:http://i.pki.goog/we1.crt
subjectAltName
DNS:bklynlibrary.org, DNS:*.bklynlibrary.org
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://c.pki.goog/we1/OmlxXM-QJxU.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : D8:09:55:3B:94:4F:7A:FF:C8:16:19:6F:94:4F:85:AB: B0:F8:FC:5E:87:55:26:0F:15:D1:2E:72:BB:45:4B:14 Timestamp : Aug 15 12:05:40.905 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:E1:CD:8A:0D:95:5F:FF:FF:79:61:20: 7F:F0:BF:57:DE:FC:91:8F:55:35:8F:FF:F3:BE:BA:5E: F5:2F:F6:6D:4C:02:20:71:A2:BF:DC:DF:4D:68:78:1C: 38:4E:13:60:2E:80:9B:5C:6D:72:20:8B:4B:0C:D2:57: FB:49:66:7F:73:6F:14 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 94:4E:43:87:FA:EC:C1:EF:81:F3:19:24:26:A8:18:65: 01:C7:D3:5F:38:02:01:3F:72:67:7D:55:37:2E:19:D8 Timestamp : Aug 15 12:05:40.851 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:F8:68:89:6C:67:91:64:87:BB:F8:09: 6E:25:D8:D5:10:46:9F:AE:BC:0A:6D:88:81:F7:AB:30: 59:71:01:4C:C7:02:21:00:C6:3D:F6:70:D5:07:82:05: 24:7F:39:C6:A7:7C:CC:F9:3E:74:8A:E5:A6:5D:9D:BE: C3:9B:F7:B1:D7:9B:8C:45
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-09-28T00:11:23+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=US O=Google Trust Services CN=WE1
Issuer
C=US O=Google Trust Services LLC CN=GTS Root R4
Valid from
2023-12-13T09:00:00+00:00
Expires
2029-02-20T14:00:00+00:00
Days remaining
876
Serial (hex)
7FF31977972C224A76155D13B6D685E3
Signature
ecdsa-with-SHA384
Public key
EC 256 prime256v1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

1D:FC:16:05:FB:AD:35:8D:8B:C8:44:F7:6D:15:20:3F:AC:9C:A5:C1:A7:9F:D4:85:7F:FA:F2:86:4F:BE:BF:96
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
90:77:92:35:67:C4:FF:A8:CC:A9:E6:7B:D9:80:79:7B:CC:93:F9:38
authorityKeyIdentifier
80:4C:D6:EB:74:FF:49:36:A3:D5:D8:FC:B5:3E:C5:6A:F0:94:1D:8C
authorityInfoAccess
CA Issuers - URI:http://i.pki.goog/r4.crt
crlDistributionPoints
Full Name: URI:http://c.pki.goog/r/r4.crl
certificatePolicies
Policy: 2.23.140.1.2.1
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Chain certificate 2

Subject
C=US O=Google Trust Services LLC CN=GTS Root R4
Issuer
C=BE O=GlobalSign nv-sa OU=Root CA CN=GlobalSign Root CA
Valid from
2023-11-15T03:43:21+00:00
Expires
2028-01-28T00:00:42+00:00
Days remaining
486
Serial (hex)
7FE530BF331343BEDD821610493D8A1B
Signature
RSA-SHA256
Public key
EC 384 secp384r1

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

76:B2:7B:80:A5:80:27:DC:3C:F1:DA:68:DA:C1:70:10:ED:93:99:7D:0B:60:3E:2F:AD:BE:85:01:24:93:B5:A7
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
basicConstraints
CA:TRUE
subjectKeyIdentifier
80:4C:D6:EB:74:FF:49:36:A3:D5:D8:FC:B5:3E:C5:6A:F0:94:1D:8C
authorityKeyIdentifier
60:7B:66:1A:45:0D:97:CA:89:50:2F:7D:04:CD:34:A8:FF:FC:FD:4B
authorityInfoAccess
CA Issuers - URI:http://i.pki.goog/gsr1.crt
crlDistributionPoints
Full Name: URI:http://c.pki.goog/r/gsr1.crl
certificatePolicies
Policy: 2.23.140.1.2.1
-----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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