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

TLSv1.2

coprosys.cz · 178.23.232.81:443

Verified

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

Subject
CN=coprosys-lvi.cz
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-11-01T04:07:43+00:00
Expires
2027-01-30T04:07:42+00:00
Days remaining
84
Serial (hex)
05F3421009E03176CDDDC2F2D656FF206AF0
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:coprosys-lvi.cz, DNS:coprosys.cz, DNS:coprosys.eu, DNS:www.coprosys-lvi.cz, DNS:www.coprosys.cz, DNS:www.coprosys.eu, DNS:wwwww.coprosys.cz

SHA-256 fingerprint

4B:D9:96:ED:F3:50:8D:68:F4:CD:D8:B8:78:39:BE:AD:12:DF:06:75:31:8D:C7:91:3F:C2:B0:0F:B7:CB:BC:AF
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
F5:0E:DE:6E:77:F7:A3:8B:FD:2D:53:CD:FB:64:57:64:DC:F3:15:B7
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:coprosys-lvi.cz, DNS:coprosys.cz, DNS:coprosys.eu, DNS:www.coprosys-lvi.cz, DNS:www.coprosys.cz, DNS:www.coprosys.eu, DNS:wwwww.coprosys.cz
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/113.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : D6:D5:8D:A9:D0:17:53:F3:6A:4A:A0:C7:57:49:02:AF: EB:C7:DC:2C:D3:8C:D9:F7:64:C8:0C:89:19:1E:9F:02 Timestamp : Nov 1 05:06:14.003 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:B0:CE:CB:AF:AF:79:4D:58:41:F6:74: 28:C5:C6:4A:F9:5F:7E:61:06:F6:B0:0D:67:DF:93:51: F4:F1:B9:CB:37:02:20:65:88:CE:67:5F:AC:B8:17:C5: 00:D6:05:C4:A6:28:85:9C:EE:2D:43:88:E8:70:5A:C6: 50:18:32:A7:2E:38:ED Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 59:6E:6C:33:86:94:B2:59:72:A2:56:C8:A0:E8:DD:90: 4A:76:E8:08:3D:DA:87:3B:01:08:38:28:14:3C:EE:59 Timestamp : Nov 1 05:06:16.244 2026 GMT Extensions: 00:00:05:00:19:8D:BD:27 Signature : ecdsa-with-SHA256 30:45:02:20:5C:51:08:12:AB:BF:A0:C7:F6:57:23:48: A9:5D:3A:3C:84:0E:EC:8F:75:B4:F8:C5:E4:7E:8A:6D: 0D:2D:05:C6:02:21:00:E1:0D:8E:C4:39:6C:01:A9:CE: E1:42:E1:E4:19:A1:9B:5D:27:B4:3B:9A:8E:B8:E7:31: E2:6B:90:A6:92:40:5B
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: ECDHE-RSA-AES128-GCM-SHA256 · Checked 2026-11-06T11:07:04+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-----
MIIF9DCCA9ygAwIBAgIRAPJLbRf52a18scn+p4eCaZ8wDQYJKoZIhvcNAQELBQAw
TzELMAkGA1UEBhMCVVMxKTAnBgNVBAoTIEludGVybmV0IFNlY3VyaXR5IFJlc2Vh
cmNoIEdyb3VwMRUwEwYDVQQDEwxJU1JHIFJvb3QgWDEwHhcNMjYwNTEzMDAwMDAw
WhcNMzIwOTAyMjM1OTU5WjAuMQswCQYDVQQGEwJVUzENMAsGA1UEChMESVNSRzEQ
MA4GA1UEAxMHUm9vdCBZUjCCAiIwDQYJKoZIhvcNAQEBBQADggIPADCCAgoCggIB
ANvGJnN78CTJdWL3+eGfsLN5TrNBJs+VH9hRXqRbwxu9sGNiB0BD1fcOxbSUQCJI
M1xE13Db+5Cw1w0s0EBYsvuIP/6joF0w8cuImbgR1OGgYbSQ4OpzI+DG8SGuTlcE
873OCS+kh3srlo6vl43M5OJg4Aeo1sfHp6kTJDoIiFBNJAY+OKfX/FUvYKuhjT+n
o49lmqmupSBI5PkBQiqrEGtWU5uxU/cQWHGu8jSjFBznZqvbNPLMXMLFxCb3WTfr
JBXXjqvWG+v4bjzxjjeAtOlU7qarRDvNOyAuQYLln904M+faKx8hnLCpJ15ZqaEg
cNlY+9MMWcC5yvL2A2j3l9+2buggZX+dOE91zYmIdawTvSZuVvlbRrAlLxIB6pwM
BjneXCjYQ8+3BCCjssbSNpZU3hTcBDdhfAlEDlYr6pEatnMdmDT5BqnKC92bd0Eh
M1fbLHioLccLCuievT8ZkPhZrq7Mii7gNXAcUEAR8+lzYal+9zTg7C5DALyVOeG/
CqfRAMn1KSHCR0NSA6P8tn/mGRlnCct5rtVCLnVySVpU6H1qGg3DgTOuskf8eahT
MiYbI5ezPJmO5ertalskQ1utp74+eDy92PI4ftHKTbq9IWhH4YZKh3WnJEIt+oQv
lYZbY8tpEroKrFB6PFGzrJIDRyts4HqvuH52RFj2zv/BAgMBAAGjgeswgegwDgYD
VR0PAQH/BAQDAgEGMBMGA1UdJQQMMAoGCCsGAQUFBwMBMA8GA1UdEwEB/wQFMAMB
Af8wHQYDVR0OBBYEFN7nW2DQIm1AKH0/DQH+pLVStFGUMB8GA1UdIwQYMBaAFHm0
WeZ7tuXkAXOACIjIGlj26ZtuMDIGCCsGAQUFBwEBBCYwJDAiBggrBgEFBQcwAoYW
aHR0cDovL3gxLmkubGVuY3Iub3JnLzATBgNVHSAEDDAKMAgGBmeBDAECATAnBgNV
HR8EIDAeMBygGqAYhhZodHRwOi8veDEuYy5sZW5jci5vcmcvMA0GCSqGSIb3DQEB
CwUAA4ICAQA8spSI95KKfn2W6GMmDpHBJSPaLbsS3W93cijJCRCYAc1fsJgL1FIL
7C0C9ecPOdcwB2fi0Dk2p94j9iTJCxmt5CFSKLRWwnXT2MMSXexVxqoVB79BdWPx
VXETkVme/qYSAuKVHh5Ps+5BixgmwS1JkjSAc+MfrUbNssVEEnH0aEiAh+rotXAV
JSP/Ye7LJPEwD9DWG72vVWbhAcuOf5OLjz57Ctk7MgQHynZ7+PlHJtajroCaIbtC
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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