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

group.one · 195.47.247.48:443

Verified

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

Subject
CN=group.one
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-09-21T02:50:22+00:00
Expires
2026-12-20T02:50:21+00:00
Days remaining
79
Serial (hex)
0670239BF097B6CD0E07D2AB24D7854A0828
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:files.group.one, DNS:group.one, DNS:www.group.one

SHA-256 fingerprint

EA:8B:C2:2F:11:82:F8:4E:43:2D:DF:A0:1E:C3:7B:06:7F:9D:80:CB:9E:51:45:85:DA:4F:53:8F:4D:0E:77:14
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
21:6D:67:D5:77:0C:39:0E:00:17:50:17:67:9D:9F:52:A8:49:41:59
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:files.group.one, DNS:group.one, DNS:www.group.one
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/41.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : AF:67:88:3B:57:B0:4E:DD:8F:A6:D9:7E:F6:2E:A8:EB: 81:0A:C7:71:60:F0:24:5E:55:D6:0C:2F:E7:85:87:3A Timestamp : Sep 21 03:48:52.725 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:B9:0F:48:25:26:11:1A:C2:A6:84:C7: 9D:E5:7A:E9:E7:24:62:5C:2D:20:14:5D:F7:63:3E:74: D7:D1:6D:0D:8F:02:20:48:45:CE:D2:80:06:D0:A5:8A: 47:D0:C0:A1:2C:EA:7B:62:25:46:0F:EA:E9:99:22:1D: 4A:93:09:03:EA:A4:71 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 8E:CA:47:0B:AC:DE:6A:F3:A2:06:B0:A4:7A:84:B7:46: FE:1F:C6:BF:95:3E:25:E6:9B:4E:E4:02:48:F3:C6:E8 Timestamp : Sep 21 03:48:52.861 2026 GMT Extensions: 00:00:05:00:11:20:CC:71 Signature : ecdsa-with-SHA256 30:45:02:21:00:97:33:97:E7:3F:F8:1B:B8:0A:2A:6C: CB:83:51:F5:FA:BA:FF:11:95:37:EC:C6:8D:2E:E1:AD: B4:12:63:FB:C1:02:20:3E:D9:D8:8F:45:08:CB:73:09: 9A:79:78:A7:E7:30:3C:DA:13:28:42:04:1C:F9:EC:27: E2:F2:27:CD:23:15:3C
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-10-02T00:27:05+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
701
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-----
MIIE2jCCAsKgAwIBAgIQTr0klH4k05SALYSlL9WzGTANBgkqhkiG9w0BAQsFADAu
MQswCQYDVQQGEwJVUzENMAsGA1UEChMESVNSRzEQMA4GA1UEAxMHUm9vdCBZUjAe
Fw0yNTA5MDMwMDAwMDBaFw0yODA5MDIyMzU5NTlaMDMxCzAJBgNVBAYTAlVTMRYw
FAYDVQQKEw1MZXQncyBFbmNyeXB0MQwwCgYDVQQDEwNZUjIwggEiMA0GCSqGSIb3
DQEBAQUAA4IBDwAwggEKAoIBAQDZ0LxwBppqh84luqMerV/eeL/fXQ7mLQQv1Lnp
WKZbyvGpx6wh6AfnslAnF6ewTkcHA+gSOoBvm3Dfm06AuGiF+KRut4fAcowqnAQQ
CW98+QPP/eOv/wug7Iyk4NkOxf2I6g2f55T6nJoOTLFcukeRq80JGQEYan+dPFr9
OGUgQK2hGKgNkW87pappsOAuUJcroYhRt5uUis4qaZireiseu32gzDJNBAiKtsvd
6HX4v25bpkRNcS/B/Gtc9kVbUpD+2PLPxdei3Tim55k4tfAEXwD2qyiPTxrTNq6l
N+AMr5g2c1dNqkOTwjxeV6L5lpP1rGiYvLnRaPlOqyZRPW+5AgMBAAGjge4wgesw
DgYDVR0PAQH/BAQDAgGGMBMGA1UdJQQMMAoGCCsGAQUFBwMBMBIGA1UdEwEB/wQI
MAYBAf8CAQAwHQYDVR0OBBYEFEAVLSZ57TIgnt+ach3WMh+BDIEMMB8GA1UdIwQY
MBaAFN7nW2DQIm1AKH0/DQH+pLVStFGUMDIGCCsGAQUFBwEBBCYwJDAiBggrBgEF
BQcwAoYWaHR0cDovL3lyLmkubGVuY3Iub3JnLzATBgNVHSAEDDAKMAgGBmeBDAEC
ATAnBgNVHR8EIDAeMBygGqAYhhZodHRwOi8veXIuYy5sZW5jci5vcmcvMA0GCSqG
SIb3DQEBCwUAA4ICAQB0ZUQWZ9/Yn9COEpo+JfecMnB0h0vwDm/M66IqXqw3LoaL
mx9lZvRTeDIS67PUeI3yCA2W6PKRD0/FE/G57lOmS+Xy5AaaL00ICGOqjNcCaMWW
8o8nevHOd4i4lqgtznE/28QwlcdJyF8yBiWHpnyjhEpmNWJURgOCOg2xpwRMBCsj
MScqYPtOhBeuYQvSwAEeTML2Ukh6uGuX4E14q65Ja8cdjF5bAldnP1eE4FBaAwsZ
G2fOqqrKV03Y85Nw2btedP1AtliQuJZs/Jo/gXxXdc7LrH3McgnpnbTiAncX7yES
hP6kzQejllqMCIt52HOjxDGWafS7Xw+DKwqmH+Eqy8dcbOuag/1AYlQoKNVK3F5q
Hh6tEDiMqQcLIibGKteE6iHo4A/bIScbzrhXUYuism42ZYzmc48FMVIH3qy4L84E
TdAH2gtxw0PAhvRVXp8HP7wfngpzsN/8xOTpeRSbM4+Qbc56G6+Bifmv6sk1ieQb
NA3wJdl4DDUuQSV8hBgx6zoI1ZSGORprDFux7c6rhc77QZMSRrEgomBeklervEve
86ylWmZ3WWHV6RLMi8xNvjd71r4EPIGgY7BZU/VPBkq+uA7Gb6mbJnFgV43uh3xy
LRFgxIAphIukwTGSMZZR+AI+Qnp0BYTWovHXozOf3H8r6hozEoT02JHn0AeTfA==
-----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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