www.babybrains.co.uk

Issued by Let's Encrypt Authority X3

About this certificate

This digital certificate with serial number 03:83:f4:e3:37:75:84:55:7d:01:0e:3e:e9:7f:58:5d:45:de was issued on by Let's Encrypt.

This certificate has already expired and will cause a warning or error message in the browser it's still listed on this site to allow you to look back on previously issued certificates. If we have found any compliance issues with this certificate they will be shown below. I hope this certificate review is providing you the detailed information in a simple form you where looking for.


We have idenified some issues with this certificate:
  • Subscriber Certificate: commonName is deprecated. (BRs: 7.1.4.2.2)

Certificate Subject

CN=www.babybrains.co.uk

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 03:83:f4:e3:37:75:84:55:7d:01:0e:3e:e9:7f:58:5d:45:de
Serial Number (int): 306239359269125264117751146651907344123358
Serial Number lenght: 138 bits, 18 octets

SubjectKeyId: fa:1f:7a:66:26:2c:34:1d:36:fb:dd:aa:36:6e:d2:7b:84:97:31:2f
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1

Fingerprint (sha1): 02:1e:67:41:9f:ee:9f:95:39:31:2a:91:f9:11:82:24:e6:bf:4e:8e
Fingerprint (sha256): 40:a9:07:1a:50:81:2c:2f:0c:83:79:4c:6d:b1:20:a9:8a:9d:5f:c7:02:a4:ef:12:b7:f7:4d:72:46:99:11:2d

Issuing Certificate URL: http://cert.int-x3.letsencrypt.org/

Revocation information

OCSP Server: http://ocsp.int-x3.letsencrypt.org

Check the revocation status for certificate www.babybrains.co.uk

1

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for www.babybrains.co.uk

Public Key Algorithm

RSA

Key Size

2048

Signature Algorithm

SHA256 with RSA

Key Usage

Digital Signature
Key Encipherment

Extended Key Usages

Server Authentication
Client Authentication

Extensions

9 extensions
No unhandled critical extensions

CA Certificate

This is not a CA certificate

Subject Alternative Names

www.babybrains.co.uk

Other certificates including the domain name babybrains.co.uk

(limited to 100 certificates)
www.babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
www.babybrains.co.uk
www.babybrains.co.uk
www.babybrains.co.uk
www.babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
www.babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
www.babybrains.co.uk
babybrains.co.uk
www.babybrains.co.uk
www.babybrains.co.uk
babybrains.co.uk
www.babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
www.babybrains.co.uk
www.babybrains.co.uk
babybrains.co.uk
babybrains.co.uk
babybrains.co.uk

Certificate

The complete raw certificate details for www.babybrains.co.uk in PEM and ASN.1 format.

Certificate (PEM)

-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Public Key (PEM)

-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAv7m7uUwVakr5Nyf/QfmM
l2YlFYYWth34q45Y2SJATVT/8eepWZhqX70xFaZHQ1GdTb3QtJiUxCqhll/HftJw
UdUqsTQHdLofwkz+jGTARktNO3YxWoPzShCfBeHlr3s1vdJprvqwxcv/MV7WZmjL
I9QV576tZamVHjLcwxNvRriO5q8okE/+NixodIiNmQcPwZ634uzfS5Joq29BtZop
DkIptE+HNhgJ8hFck8xW5n9iT2NpjQC+G48oqXvsq+xoM/wT0TGC2DiDyibknXVW
pe8QF5Sxb0oA8oC1VgkU2g4TljAUJonLGZY2wTp51G99sFWQn0mgWS4tcYf1Mg7d
VwIDAQAB
-----END PUBLIC KEY-----

ASN.1 decoded

 [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . [c:2|t:0|true] OtherName 
 . . . . . . . . . . . . [c:0|t:2|false] INTEGER 2
 . . . . . . . . [c:0|t:2|false] INTEGER 306239359269125264117751146651907344123358
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.113549.1.1.11 (sha256WithRSAEncryption)
 . . . . . . . . . . . . [c:0|t:5|false] NULL 
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:17|true] SET, SET OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.4.6 (countryName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'US'
 . . . . . . . . . . . . [c:0|t:17|true] SET, SET OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.4.10 (organizationName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'Let's Encrypt'
 . . . . . . . . . . . . [c:0|t:17|true] SET, SET OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.4.3 (commonName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'Let's Encrypt Authority X3'
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2018-09-08 08:42:10 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2018-12-07 08:42:10 +0000 UTC
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:17|true] SET, SET OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.4.3 (commonName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'www.babybrains.co.uk'
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.113549.1.1.1 (rsaEncryption)
 . . . . . . . . . . . . . . . . [c:0|t:5|false] NULL 
 . . . . . . . . . . . . [c:0|t:3|false] BIT STRING (2160 bits)
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:2|false] INTEGER 24203104750404356849162173487749043321907433706785105417397149040760238142772376534928094454914503892438951443007257785660612641024357057049208921053980856354334060855531085919509806171990176713068833080652377023294830244576204184769432661302789632877325937329454416024452480744305994606736022020541047157563370267534194118893136701689748475635193175568381636163074206889461603158795899149106413145503542005900546815160016377388385228438383614055582734315692719071034719126630675600661010459806942025251410745304723862862745674028963402332581282870847534389453907313719235964299377216080825549173147075596366650465623
 . . . . . . . . . . . . . . . . . . . . [c:0|t:2|false] INTEGER 65537

 . . . . . . . . [c:2|t:3|true] ORAddress 
 . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.15 (keyUsage)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:1|false] BOOLEAN true
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (4 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:3|false] BIT STRING (3 bits)
							05a0
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.37 (extKeyUsage)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (22 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.3.1 (serverAuth)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.3.2 (clientAuth)
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.19 (basicConstraints)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:1|false] BOOLEAN true
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (2 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.14 (subjectKeyIdentifier)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (22 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (20 bytes)
							fa1f7a66262c341d36fbddaa366ed27b8497312f
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.35 (authorityKeyIdentifier)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (24 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:0|false] OtherName a84a6a63047dddbae6d139b7a64565eff3a8eca1
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.1.1 (authorityInfoAccess)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (99 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.48.1 (ocsp)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:6|false] IA5String 'http://ocsp.int-x3.letsencrypt.org'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.48.2 (caIssuers)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:6|false] IA5String 'http://cert.int-x3.letsencrypt.org/'
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.17 (subjectAltName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (24 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.babybrains.co.uk'
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.32 (certificatePolicies)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (246 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.23.140.1.2.1 (Domain Validation Certificates Policy)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.4.1.44947.1.1.1
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.2.1 (cps)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:22|false] IA5String 'http://cps.letsencrypt.org'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.2.2 (unotice)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:12|false] UTF8String 'This Certificate may only be relied upon by Relying Parties and only in accordance with the Certificate Policy found at https://letsencrypt.org/repository/'
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.4.1.11129.2.4.2
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (246 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (243 bytes)
							00f1007600c1164ae0a772d2d4392dc80ac10770d4f0c49bde991a4840c1fa075164f6336000000165b88f67ec0000040300473045022100fdb926a381ebefc250a8625b4904763440d8b97a76a33f05930e12e30fbd3838022002a850ad5903f27ef6c445e17eccc199b6e21ee590904710c9d86f29a93cc7f9007700293c519654c83965baaa50fc5807d4b76fbf587a2972dca4c30cf4e54547f47800000165b88f67ff0000040300483046022100e7d1ed79a80a6e4982f62d2649dee968a5053ee9340e76bc821294eb14f9021e022100f7379423d759d587323e5a162717618b41079c19603dc94f9c8a0a077a3c5c61
 . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.113549.1.1.11 (sha256WithRSAEncryption)
 . . . . . . . . [c:0|t:5|false] NULL 
 . . . . [c:0|t:3|false] BIT STRING (2048 bits)
		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