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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

o2.com · 20.162.150.90:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. Peer certificate CN=`www.o2.co.uk' did not match expected CN=`o2.com'

Certificate verification failed

Subject
jurisdictionC=GB businessCategory=Private Organization serialNumber=01743099 C=GB L=Reading O=TELEFONICA UK LIMITED CN=www.o2.co.uk
Issuer
C=US O=DigiCert Inc CN=Thawte EV RSA CA G2
Valid from
2026-09-21T00:00:00+00:00
Expires
2027-04-07T23:59:59+00:00
Days remaining
187
Serial (hex)
093EB3BE77038660DA12FEF42F250A8A
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:www.o2.co.uk, DNS:o2.co.uk

SHA-256 fingerprint

C4:7B:4C:01:5F:5B:6F:29:54:B5:23:93:B5:D1:29:F5:92:1A:DE:9A:7E:1A:3B:DB:87:8A:BF:49:20:88:E3:33
Certificate extensions & PEM
authorityKeyIdentifier
6C:2E:E4:61:B4:C3:B9:BD:F0:CA:AD:A6:C1:68:7A:B8:D4:CC:1D:A0
subjectKeyIdentifier
33:C5:38:92:86:61:51:CD:A2:3F:6E:21:28:50:7F:E1:6C:7C:DF:E6
subjectAltName
DNS:www.o2.co.uk, DNS:o2.co.uk
certificatePolicies
Policy: 2.16.840.1.114412.2.1 Policy: 2.23.140.1.1 CPS: http://www.digicert.com/CPS
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
crlDistributionPoints
Full Name: URI:http://crl3.digicert.com/ThawteEVRSACAG2.crl Full Name: URI:http://crl4.digicert.com/ThawteEVRSACAG2.crl
authorityInfoAccess
OCSP - URI:http://ocsp.digicert.com CA Issuers - URI:http://cacerts.digicert.com/ThawteEVRSACAG2.crt
basicConstraints
CA:FALSE
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 4C:63:DC:98:E5:9C:1D:AB:88:F6:1E:8A:3D:DE:AE:8F: AB:44:A3:37:7B:5F:9B:94:C3:FB:A1:9C:FC:C1:BE:26 Timestamp : Sep 21 09:39:01.354 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:AF:D7:0D:23:8E:75:3E:2B:34:31:40: 3C:71:AD:7D:9F:DA:DE:41:B0:A1:C4:21:C3:95:48:CF: 3F:3B:F2:06:8E:02:20:23:E8:4C:47:C8:C2:A5:9F:63: D6:7E:FC:07:4C:6A:68:BD:F6:FC:0B:B5:9C:3F:ED:D1: 30:26:BD:E7:B7:89:C7 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 44:C2:BD:0C:E9:14:0E:64:A5:C9:4A:01:93:0A:5A:A1: BB:35:97:0E:00:EE:11:16:89:68:2A:1C:44:D7:B5:66 Timestamp : Sep 21 09:39:01.424 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:7E:32:72:D1:AF:6B:6D:82:A9:82:BF:44: 69:B3:CB:C5:C1:C2:04:34:8D:95:49:0D:57:A5:61:18: CD:A6:B7:77:02:21:00:BF:1D:3F:47:E4:59:AE:A3:E8: 64:2A:15:6F:08:C4:2C:5E:50:F8:76:5D:62:D2:6B:A6: 4E:8A:8B:43:6B:6F:78 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 : Sep 21 09:39:01.441 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:7E:27:B1:28:58:4A:74:C7:E2:D6:8E:1A: D0:F3:66:BB:9B:E8:CF:B1:6E:80:A5:AB:BE:8A:70:A1: F1:F1:A0:6A:02:21:00:90:5C:A5:5A:0D:EB:22:4A:7D: B5:D5:B6:C2:91:73:0F:9F:EC:0C:5F:FC:76:E2:6C:F0: 02:62:57:E7:02:F9:80
-----BEGIN CERTIFICATE-----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==
-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-10-02T18:22:59+00:00

Server-presented chain · 1 additional certificate

Chain certificate 1

Subject
C=US O=DigiCert Inc CN=Thawte EV RSA CA G2
Issuer
C=US O=DigiCert Inc OU=www.digicert.com CN=DigiCert Global Root G2
Valid from
2020-07-02T12:43:02+00:00
Expires
2030-07-02T12:43:02+00:00
Days remaining
1368
Serial (hex)
07C2C6D32C6F0E0AABAC0DD0F9FCD5B3
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

32:86:69:14:12:F3:0E:CE:5C:06:5F:D6:2F:43:92:A4:76:2D:1E:77:81:53:38:35:9D:F3:90:29:9F:BD:61:EF
Certificate extensions & PEM
subjectKeyIdentifier
6C:2E:E4:61:B4:C3:B9:BD:F0:CA:AD:A6:C1:68:7A:B8:D4:CC:1D:A0
authorityKeyIdentifier
4E:22:54:20:18:95:E6:E3:6E:E6:0F:FA:FA:B9:12:ED:06:17:8F:39
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
basicConstraints
CA:TRUE, pathlen:0
authorityInfoAccess
OCSP - URI:http://ocsp.digicert.com
crlDistributionPoints
Full Name: URI:http://crl3.digicert.com/DigiCertGlobalRootG2.crl Full Name: URI:http://crl4.digicert.com/DigiCertGlobalRootG2.crl
certificatePolicies
Policy: X509v3 Any Policy CPS: https://www.digicert.com/CPS User Notice: Explicit Text: Any use of this Certificate constitutes acceptance of the Relying Party Agreement located at https://www.digicert.com/rpa-ua
-----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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