Dart Formatter
Format and beautify Dart code following Dart style guidelines
Dart Formatting Tips
- Follow the official Dart style guide: use trailing commas for better formatting of parameter lists.
- Use 2-space indentation as recommended by the Dart style guide.
- Prefer single quotes for strings unless interpolation is needed, then use double quotes.
Professional Dart Formatter Processing Features
Everything you need to work with Dart Formatter data efficiently and professionally
Syntax Validation
Detect unclosed braces, brackets, and parentheses with precise error reporting for Dart code.
Beautify Dart Code
Transform messy Dart code into clean, consistently indented code following the Dart style guide.
Widget Formatting
Properly format deeply nested Flutter widget trees with readable indentation and trailing commas.
Async/Await Handling
Correctly format async functions, Future chains, and Stream operations with proper alignment.
Fast Processing
Format Dart files up to 10MB instantly with client-side processing, no server round-trips needed.
Smart Indentation
Intelligent indentation for classes, mixins, extensions, and enum declarations.
How It Works
Simple steps to process your Dart Formatter like a pro
Paste Your Dart Code
Paste your Dart source code into the input area, or load a sample to get started.
Customize Options
Choose indentation size to match your project conventions.
Format & Review
Click the format button to beautify your Dart code and review the clean output.
Copy or Download
Copy the formatted code to your clipboard or download it as a file for your project.
Professional Dart Formatter Formatter & Validator
Dart Formatter processing runs entirely in your browser — no uploads, no accounts, no limits.
Processing method
Use this tool’s examples, syntax limits and source documentation to understand its output.
Key Technical Features:
- • Dart syntax-aware parsing with brace matching
- • Support for Dart 3 features including records and patterns
- • Intelligent indentation for widgets and nested expressions
- • Client-side processing for maximum security and speed
- • Support for large files up to 10MB
Processing and output
Check the stated processing method and compare the result with your input before using it.
Security & Privacy:
- • 100% client-side processing - data never sent to servers
- • No tracking, cookies or data collection
- • HTTPS encryption for secure connections
- • No data stored or cached after processing
- • GDPR and CCPA compliant approach
Why Professionals Choose EZ Formatter
Your data stays in your browser
Frequently Asked Questions
Common questions about Dart Formatter formatting answered
Yes, our Dart formatter is completely free with no registration required. All processing happens in your browser.
Yes, our formatter properly handles deeply nested Flutter widget trees with consistent indentation and trailing commas.
Yes, it supports modern Dart features including records, patterns, sealed classes, and class modifiers.
No. The formatter only adjusts whitespace and indentation. It never modifies identifiers, types, or logic.
By default, it follows the official Dart style guide with 2-space indentation, consistent spacing, and proper line breaking.
The official dart style (dart format, the Dart team's canonical formatter): 2-space indent, 80-column width, and trailing commas that force argument lists to split one-per-line. Dart's formatter is intentionally non-configurable - the language team's position is that one style makes the ecosystem uniform, like Go.
In dart format, an argument list with a trailing comma always explodes vertically (one argument per line), while without it the formatter greedily fits everything on one line. Flutter developers exploit this: adding a trailing comma after widget arguments produces the readable multi-line widget trees the Flutter style guide shows.
Nested constructors indent one level per depth with closing parens/brackets aligned to their opening line; cascade sections (thing..first()..second()) keep one section per line when wrapped, with the .. aligned. Collection literals (lists of widgets) get the same one-element-per-line treatment with trailing commas.
Authoritative References
Standards and official documentation that define the formats this tool works with.
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