Common Certificate Subject OIDs

Here’s a list of common X.509 digital certificate Subject OIDs (Object Identifiers) you’ll typically see in the Subject Distinguished Name (DN) of a certificate.


Core Subject DN Attributes (Most Common)

Attribute Name Abbreviation OID Description
Common Name CN 2.5.4.3 Usually the hostname (e.g., www.example.com)
Organization O 2.5.4.10 Legal organization name
Organizational Unit OU 2.5.4.11 Department within organization
Country C 2.5.4.6 2-letter ISO country code
State / Province ST 2.5.4.8 State or province
Locality L 2.5.4.7 City
Street Address STREET 2.5.4.9 Street address
Postal Code postalCode 2.5.4.17 ZIP / postal code
Serial Number serialNumber 2.5.4.5 Business registration number

Personal Identity Attributes

Attribute Name OID Description
Given Name 2.5.4.42 First name
Surname 2.5.4.4 Last name
Initials 2.5.4.43 Middle initials
Title 2.5.4.12 Job title
Generation Qualifier 2.5.4.44 Jr., Sr., III
Pseudonym 2.5.4.65 Alternate name

Email & Domain Related

Attribute Name OID Notes
Email Address 1.2.840.113549.1.9.1 PKCS#9 emailAddress (legacy, but common)
Domain Component 0.9.2342.19200300.100.1.25 Used in LDAP-style DNs
User ID (UID) 0.9.2342.19200300.100.1.1 Often used in LDAP directories

Business / EV Certificate Attributes

Common in Extended Validation (EV) certificates:

Attribute Name OID
Jurisdiction of Incorporation – Country 1.3.6.1.4.1.311.60.2.1.3
Jurisdiction of Incorporation – State 1.3.6.1.4.1.311.60.2.1.2
Jurisdiction of Incorporation – Locality 1.3.6.1.4.1.311.60.2.1.1
Business Category 2.5.4.15

Subject Alternative Name (SAN) OIDs (Extension)

Technically not in the Subject DN, but extremely important:

Extension OID
Subject Alternative Name 2.5.29.17

Inside SAN you commonly find:

  • DNS Name
  • IP Address
  • Email
  • URI

Common CA-Specific OIDs

Some Certificate Authorities define their own:

Organization Example OID Prefix
Microsoft 1.3.6.1.4.1.311.*
DigiCert 2.16.840.1.114412.*
Entrust 2.16.840.1.114028.*

Example Subject DN

Example certificate subject:

CN=www.example.com
O=Example Corp
OU=IT Department
L=Chicago
ST=Illinois
C=US

Which corresponds to:

2.5.4.3 = www.example.com
2.5.4.10 = Example Corp
2.5.4.11 = IT Department
2.5.4.7 = Chicago
2.5.4.8 = Illinois
2.5.4.6 = US

If you'd like, I can also provide:

  • A list of common X.509 extension OIDs
  • OIDs related to Key Usage / Extended Key Usage
  • A mapping table formatted specifically for Chilkat usage
  • Or sample code to enumerate Subject OIDs using Chilkat

Just let me know.