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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

mmu.ac.uk · 52.211.85.12:443

Verified

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

Subject
CN=mmu.ac.uk
Issuer
C=US O=Let's Encrypt CN=YR1
Valid from
2026-09-11T08:10:16+00:00
Expires
2026-12-10T08:10:15+00:00
Days remaining
36
Serial (hex)
06AF9432BCB01CD33C4AEE543D7F20084B80
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:mmu.ac.uk

SHA-256 fingerprint

AB:B9:BA:A9:E6:01:AE:4E:DF:1D:05:D6:C8:41:68:36:6E:35:AE:3F:EA:93:A7:E7:FD:A6:CB:6D:C6:10:18:8B
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
2C:E1:B8:2E:ED:BA:73:75:04:CE:81:69:E5:C7:04:1E:67:E4:8B:DB
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:mmu.ac.uk
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr1.c.lencr.org/1.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : A8:26:CB:E3:0A:C6:35:12:46:53:3F:E0:65:F1:4F:19: D9:6E:19:08:13:C4:1D:D9:6D:79:00:B3:12:3C:55:27 Timestamp : Sep 11 09:08:46.949 2026 GMT Extensions: 00:00:05:00:31:1E:1A:40 Signature : ecdsa-with-SHA256 30:44:02:20:0D:5F:49:9A:2D:2A:DC:60:7B:6F:A0:32: A1:09:CB:27:2D:BD:FE:DF:EF:5F:D6:FE:8B:DE:F0:F8: 26:B7:8A:0F:02:20:5E:40:00:AE:E3:31:27:4E:FD:A5: A2:79:05:38:AF:FB:22:AE:BA:BC:AD:1F:91:21:09:B3: 71:B3:A3:9A:4F:C2 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : C2:31:7E:57:45:19:A3:45:EE:7F:38:DE:B2:90:41:EB: C7:C2:21:5A:22:BF:7F:D5:B5:AD:76:9A:D9:0E:52:CD Timestamp : Sep 11 09:08:48.230 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:18:23:9B:5D:BA:4E:94:AB:2A:78:38:AD: 5E:AE:D9:79:88:99:58:B3:A0:57:13:33:17:88:33:C0: B1:C1:D3:98:02:20:37:D1:7E:E6:50:C7:19:09:B0:83: 81:CA:2F:71:48:4A:FF:29:3F:8D:2B:8A:97:4A:BE:2F: B1:48:AE:EB:43:21
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-11-03T20:04:53+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
669
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
2130
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-----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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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