ini file extension introduction?

ini file is file extension, an data format for configuration and setup files for software applications. These files contains configuration values very popularly used by windows Operating System.

ini files looks like properties file with comments, headers

ini is abbreviated Initialize values as language and it is a new file format. It is used for specifying data in configurations similar to text files . Usually each software or application has some configuration data, We used to have property file with key and value pairs like key=value.The property files are not suitable when there is complex structure of configuration. INI is suitable for representing data in hash table format and easy to read and write the data using various programming languages.

windows provides two Ini files, system.ini, windows.ini files by default, So many applications during shipping the product to client has configurations in ini format

Advantages of INI file extension

  • It is human readable for simple configuration and settings
  • Support all popular languages - GO,Java,Python, JavaScript etc.
  • Supports Comments
  • Maintainable
  • Read and write capabilities
  • content of this files looks like windows init format


  • Numbers like NAN and infinity are not supported
  • No support for binary data
  • Complex values ike table are not supported

INI use cases

  • INI can be used in many type of projects for configuration settings
  • Windows uses configuration settings for drivers,keyboards,mouses
  • Configuration and settings of the software applications

INI file extension

Initialise configuration in a file with extension .INI, You can use any IDE or text editor to open this file.

Ini File extension rules

  • Ini files extension is .ini by default
  • file supports UTF-8 encoding format only
  • Supports whitespaces, tabs and newlines asci code

MIME format type - text/plain

MIME is abbreviated as Multipurpose Internet Mail Extensions which is a format specified in request and response that is transferred between client and server across internet. Content-Type and accept headers in a request object are specified with this format following is the mime type for this documents


and request contains the below value for INI data sending over the internet

Content-type : text/plain


All the popular IDE supports the INI file extension and also provides plugins to validate the INI file content.

  • Notepad++
  • Eclipse
  • Visual Studio Code