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

stuycs.org · 185.199.109.153:443

Verified

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

Subject
CN=stuycs.org
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-08-29T12:02:52+00:00
Expires
2026-11-27T12:02:51+00:00
Days remaining
58
Serial (hex)
05ADC271D600FC4B448BF840627D5037332D
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:stuycs.org, DNS:www.stuycs.org

SHA-256 fingerprint

7B:38:23:9B:16:66:80:0A:A0:AA:04:62:D0:D2:33:DE:4E:E2:B2:83:86:EB:CE:04:9D:1F:45:6A:FD:9B:F5:7D
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
58:C9:B2:AA:68:E6:A5:48:CC:D8:2B:E8:42:B2:BF:7F:BE:45:66:68
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:stuycs.org, DNS:www.stuycs.org
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/46.crl
ct_precert_scts
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 29 13:01:22.678 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:F7:57:0A:EC:A4:75:A5:90:54:DD:6D: F3:EF:F8:A9:A7:25:78:16:8E:E3:21:6D:D8:2F:21:41: A6:8E:87:40:B7:02:20:6C:24:CD:AB:9D:C2:CC:0E:9D: 4B:42:3C:F0:BC:85:2F:BA:34:BC:63:B0:C4:01:3F:EA: 79:30:5B:C5:5E:27:CF Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 6C:FE:50:19:43:A8:5E:A9:16:BC:52:D1:33:E4:DC:C9: 1E:F1:41:1C:7D:25:84:20:D1:73:80:9E:18:18:EB:3A Timestamp : Aug 29 13:01:23.032 2026 GMT Extensions: 00:00:05:00:29:9A:CE:F5 Signature : ecdsa-with-SHA256 30:45:02:20:78:1B:DE:58:83:EA:BF:B8:C7:9A:B5:99: F4:A0:37:D9:06:D9:8C:F2:63:2F:A8:8D:88:9F:05:8C: 31:42:4B:D8:02:21:00:DD:AA:89:10:C9:7C:7C:83:72: C9:29:5C:B2:F5:56:29:FE:A9:8E:2F:0F:8B:5C:07:75: 4D:F3:8D:DF:EB:40:13
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-09-30T03:28:45+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
703
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
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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r6tcZZaAwUQm+jQyeWdV+2hv9deOYFmKeQyjjcSrN5Nadrw+L9DZJLbA1HqeNvLh
BgqpP0fvJq2N6EtD574N6eMI7uMsJTnji2UDz9el5XLSv9fqJMuDQtYVb2oTNoKp
oUqhxPVC0aq4eG5MESaIdn8b5ZGSSeAJLMHXljEdlNza+ncfkviXk1POLnnFdvx8
/gk6M374WbLWFXw8N141B/Rl/tINGfl1TxOIiqtiMYkL02RSGb1kq34BL9NPP27z
RGMuHGnzS3hFIrRTfKxrzUZ9RzQWzEG3K6fJ3r2nqSltkeytis9DIBoFY9VmVyjL
M71DMi+y1+TRSJVClEMwvA4yL++7q9XZx5r5wBRWB4kQTKH5qyoZnDw7iiuh1lID
yDFx8r7i9vIJU5HS3moZLkYWAOilMaV9N56A9Bgb6dNcHkvg3NoaYA==
-----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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