.ini

What is a .ini file?

INI is a simple configuration format using sections and key-value pairs — common in Windows applications since version 1.0.

Safe format
Type Data
By Microsoft
MIME text/plain

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What is it

You're looking at an .ini file — one of the oldest and simplest configuration formats still in active use. INI files use sections in square brackets, keys and values separated by equals signs, and comments starting with semicolons. Windows has used them since version 1.0 in 1985, and they persist because simplicity is surprisingly hard to kill.

INI has no formal specification — different parsers handle edge cases differently (whitespace around equals signs, duplicate keys, nested sections). It can't express complex data structures: no arrays, no nested objects, no data types beyond strings. For simple key-value configuration, that's a feature, not a bug. PHP's php.ini, Python's setup.cfg, MySQL's my.cnf, and Git's .gitconfig all use INI-style syntax.

Any text editor opens .ini files. VS Code provides syntax highlighting. The format is human-readable without any learning curve — if you can read `color = blue`, you can read an INI file. For modern projects that need nested configuration, TOML is INI's spiritual successor — same readability, more structure.

Technical details
Full Name
Initialization File
MIME Type
text/plain
Developer
Microsoft
Magic Bytes
N/A
Safety
.ini is a known, safe format.
What opens it
Any text editor
FREE All
FAQ
What's the difference between INI and TOML?
TOML is a modern evolution of INI that adds typed values (integers, booleans, dates, arrays), nested tables, and a formal specification. INI is simpler but less capable. For new projects, TOML is the better choice.
Why do so many programs still use INI files?
Simplicity and inertia. INI files are human-readable, easy to parse, and every programming language has an INI parser. For flat key-value configuration, the format does exactly what's needed without overhead.
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