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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.optisprint.net · 212.233.128.16:443

Verified

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

Subject
CN=mail.optisprint.net
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-10-03T20:03:05+00:00
Expires
2027-01-01T20:03:04+00:00
Days remaining
88
Serial (hex)
050F560DDC28E8850B50A4BC686BF299A923
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:mail.optisprint.net

SHA-256 fingerprint

6F:04:B7:8A:F9:D9:16:60:C1:51:74:73:EF:00:A4:B7:35:8B:6E:03:B3:92:27:D1:7E:56:3D:55:25:4F:04:C4
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
B6:0A:72:66:09:3B:AE:11:BE:23:BF:76:FC:6F:81:0F:2D:7B:4A:2F
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:mail.optisprint.net
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 : 1C:9F:68:2C:E9:FA:F0:45:69:50:F8:1B:96:8A:87:DD: DB:32:10:D8:4C:E6:C8:B2:E3:82:52:4A:C4:CF:59:9F Timestamp : Oct 3 21:01:35.174 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:C6:97:B4:F8:C8:11:44:D2:9A:08:26: 20:96:FB:77:47:22:1E:F5:6F:BE:4E:54:4F:1D:96:33: D8:09:53:C2:F4:02:21:00:9A:BB:83:B4:79:3D:38:60: B3:AA:E9:BC:0F:16:E5:BD:C5:94:F0:37:76:06:67:DC: C7:BE:00:0A:E8:1F:CE:6B Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1A:8B:9D:6B:8D:D7:91:D1:CD:05:49:ED:B6:03:55:D6: 06:B6:4F:AD:30:DB:71:FE:78:8F:0F:C7:C8:FB:C4:B1 Timestamp : Oct 3 21:01:35.580 2026 GMT Extensions: 00:00:05:00:05:06:19:33 Signature : ecdsa-with-SHA256 30:45:02:21:00:C0:94:08:DC:E4:F0:B6:BF:A2:EA:44: 4D:E3:F1:C7:2E:5B:14:5F:37:52:DC:A4:1D:C9:D7:BD: 75:35:FD:5D:90:02:20:35:5D:D8:60:5F:FD:8F:B3:12: F4:F5:00:DE:81:FA:B7:10:8B:A3:D8:2D:F9:35:F7:3B: 07:86:46:6D:E0:3D:59
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-10-05T05:43:13+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
698
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
2159
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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