.dart

What is a .dart file?

Dart is Google's language for Flutter — build cross-platform mobile, web, and desktop apps from a single codebase.

Use caution
Type Code
By Google
MIME text/x-dart

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What is it

Dart exists because of Flutter, and Flutter exists because of Dart. Google's UI framework needed a language that could compile to native ARM code, transpile to JavaScript, and provide hot reload during development. Dart checks all three boxes. The language is unremarkable by design — it reads like Java meets TypeScript, with null safety, async/await, and a familiar class-based syntax.

Flutter is Dart's killer app. Write one codebase, deploy to iOS, Android, web, Windows, macOS, and Linux. Flutter's widget-based architecture and Dart's hot reload (see changes instantly without restarting the app) make mobile development dramatically faster. Google's own apps (Google Pay, Stadia, Google Ads) use Flutter.

VS Code and Android Studio both have excellent Dart/Flutter extensions. `dart create` scaffolds new projects. The `pub` package manager handles dependencies. For web development without Flutter, Dart compiles to JavaScript and can replace TypeScript, though it hasn't gained much traction in that space.

Technical details
Full Name
Dart Source
MIME Type
text/x-dart
Developer
Google
Magic Bytes
N/A
Safety
.dart requires caution. Source code file. Safe to read.
What opens it
VS Code (+ Dart extension)
FREE Windows / Mac / Linux
Android Studio
FREE Windows / Mac / Linux
Any text editor
FREE Windows / Mac / Linux
FAQ
Do I need to learn Dart to use Flutter?
Yes. Flutter uses Dart exclusively. The good news: Dart is easy to learn if you know Java, JavaScript, or TypeScript. Most developers pick it up in a few days.
Is Dart only for Flutter?
Dart can be used for server-side code, command-line tools, and web development independently. But in practice, 95%+ of Dart usage is through Flutter for cross-platform app development.
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