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

42.pl · 79.98.145.42:443

Verified

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

Subject
CN=42.pl
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-08-29T01:43:59+00:00
Expires
2026-11-27T01:43:58+00:00
Days remaining
62
Serial (hex)
054D89A94FC6597A4F8DBDF1DBD908F46D59
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:42.pl, DNS:www.42.pl

SHA-256 fingerprint

E1:DE:10:E0:97:F9:3B:A9:FE:FE:DE:CE:62:B8:E3:88:EF:67:66:60:1C:0B:9A:05:57:3C:44:B8:87:4B:79:32
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
18:3B:7F:7F:74:46:93:58:63:D3:54:C5:BD:D4:15:40:88:96:46:1D
authorityKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
authorityInfoAccess
CA Issuers - URI:http://yr2.i.lencr.org/
subjectAltName
DNS:42.pl, DNS:www.42.pl
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/90.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 46:AF:86:3D:3B:3E:E5:9F:A5:77:DE:A8:24:5D:36:B0: D9:ED:22:A2:23:F4:61:77:41:22:94:52:EE:95:50:5F Timestamp : Aug 29 02:42:29.952 2026 GMT Extensions: 00:00:05:00:1F:F7:BF:E4 Signature : ecdsa-with-SHA256 30:45:02:20:6B:97:42:4A:16:21:18:21:36:34:34:7D: C6:5C:83:F4:70:EB:60:EC:BF:E6:AF:13:1F:FF:4F:4A: D9:F0:41:1C:02:21:00:AF:8E:EC:89:DB:EF:D2:52:22: D0:29:57:E4:15:9C:79:C5:9E:22:08:A3:9B:B6:8E:66: C7:D1:8C:68:73:91:EC 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 29 02:42:29.963 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:5F:90:2B:20:AA:AB:28:D6:EB:81:78:F0: 79:F8:75:34:2E:0F:4F:91:AD:A4:AA:CF:68:8B:02:80: 9B:ED:7C:92:02:21:00:D1:4A:C4:97:65:A3:6B:32:B9: 6C:C1:8C:4A:94:9D:42:20:44:2E:7F:87:3C:AB:79:94: 42:50:B8:1E:D1:86:E2
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: ECDHE-RSA-AES256-GCM-SHA384 · Checked 2026-09-25T18:54:31+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YR2
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
708
Serial (hex)
4EBD24947E24D394802D84A52FD5B319
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

23:8B:85:A0:09:9C:65:B9:70:47:7D:57:24:F1:A1:D4:75:CE:50:58:CF:FE:4E:FA:87:33:89:9B:DB:86:3C:47
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
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
2169
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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