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

fastnet.com.ar · 181.88.192.127:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. SSL operation failed with code 1. OpenSSL Error messages: error:0A000086:SSL routines::certificate verify failed
The certificate has expired.

Certificate verification failed

Subject
CN=fastnet.com.ar
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-07-02T03:03:37+00:00
Expires
2026-09-30T03:03:36+00:00
Days remaining
-3
Serial (hex)
05DA56FF09A5E6F257D2E4EF117633CE229E
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:fastnet.com.ar

SHA-256 fingerprint

8F:4A:57:B3:D8:3F:E5:FF:76:DE:57:BD:E1:5A:6D:A8:76:20:8C:F7:C5:13:D3:F8:15:CF:27:6F:36:FC:AE:AC
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
74:9E:D2:DE:D1:D2:3B:0C:D4:7A:F7:1B:35:FB:B2:F7:CE:0B:4F:5D
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:fastnet.com.ar
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/31.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 : Jul 2 04:02:07.856 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:8B:66:4A:B2:BE:44:62:5E:9E:11:43: EF:CD:CB:CE:E6:BF:AF:E6:15:16:12:BD:7A:66:D2:06: 68:58:CA:41:2C:02:21:00:C4:4A:8F:3B:61:3A:30:9E: B7:D9:3F:C1:F8:89:19:26:5B:58:96:F7:9C:A4:05:3F: 2D:2A:DE:B2:0E:C8:5A:11 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 26:E3:64:6E:58:69:21:23:BC:34:3F:47:24:35:9B:37: 92:CD:24:5A:88:D8:15:D3:93:33:FD:99:18:AB:47:23 Timestamp : Jul 2 04:02:07.495 2026 GMT Extensions: 00:00:05:00:24:68:B0:1D Signature : ecdsa-with-SHA256 30:46:02:21:00:E5:D4:F8:40:02:4F:02:57:99:76:B1: 32:C9:56:98:00:C3:44:13:65:47:D8:F0:E0:BE:F6:61: 8A:9D:28:1E:16:02:21:00:EA:2E:7A:41:0F:74:9E:77: 26:AB:65:8E:B5:2F:0D:3C:0F:9A:52:70:75:C3:F5:D2: BD:7F:2C:FA:48:80:FC:7A
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-10-02T09:56:55+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
701
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
2162
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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