Prettier vs JS-Beautify vs Uncrustify: Best Formatter? | Web Formatter Blog
Prettier vs JS-Beautify vs Uncrustify: Best Formatter?
A comprehensive comparison of three popular code formatters to help you choose the right one for your projects.
Introduction to Code Formatters
Code formatters are essential tools in modern software development that automatically restructure your code to follow consistent style rules. They eliminate debates about code style, save time during code reviews, and help maintain a clean, readable codebase.
In this comprehensive comparison, we'll examine three popular code formatters:
- Prettier: An opinionated code formatter with support for many languages
- JS-Beautify: A JavaScript-focused beautifier with extensive configuration options
- Uncrustify: A highly configurable source code beautifier for C-like languages
We'll analyze their features, strengths, weaknesses, and ideal use cases to help you determine which formatter best suits your project needs.
Prettier
Prettier has gained immense popularity since its introduction in 2017, becoming the de facto standard for JavaScript and front-end code formatting.
Key Features
- Opinionated formatting: Prettier has strong opinions about code style and offers minimal configuration options
- Multi-language support: Formats JavaScript, TypeScript, CSS, HTML, JSON, Markdown, and more
- AST-based parsing: Parses code into an abstract syntax tree for more reliable formatting
- Plugin ecosystem: Supports extensions for additional languages and custom rules
- IDE integration: Seamless integration with VS Code, WebStorm, and other popular editors
Here's an example of Prettier formatting JavaScript code:
Pros and Cons
Pros
- Minimal configuration needed - works well out of the box
- Consistent formatting across different languages
- Strong community support and regular updates
- Excellent documentation and integration options
- Handles complex formatting scenarios well (JSX, long chains)
Cons
- Limited customization options by design
- May not satisfy developers who prefer fine-grained control
- Can be slower than some alternatives for very large files
- Occasionally makes controversial formatting decisions
Best Use Cases
Prettier is ideal for:
- JavaScript/TypeScript projects, especially those using React or other JSX frameworks
- Teams that want to eliminate style debates and adopt a standard quickly
- Projects that use multiple front-end languages (JS, CSS, HTML, etc.)
- Developers who prefer a "set it and forget it" approach to formatting
- Open-source projects that want to maintain consistent style across contributors
JS-Beautify
JS-Beautify has been around longer than Prettier and offers more configuration options for JavaScript, HTML, and CSS formatting.
Key Features
- Highly configurable: Offers numerous options to customize formatting behavior
- Language support: Focuses on JavaScript, HTML, and CSS
- Multiple interfaces: Available as a CLI tool, library, or online service
- Editor plugins: Integrates with popular editors like VS Code and Sublime Text
- Mature codebase: Well-established with years of development history
Here's an example of JS-Beautify formatting JavaScript code:
Pros and Cons
Pros
- Extensive configuration options for fine-tuning format rules
- Faster performance on large files compared to Prettier
- Stable and mature with a long development history
- Less opinionated, allowing teams to define their own style
- Good backward compatibility
Cons
- Limited language support compared to Prettier
- Configuration can be complex and time-consuming
- Less active development in recent years
- Not as well-suited for modern JavaScript frameworks
- Doesn't handle some complex formatting scenarios as elegantly
Best Use Cases
JS-Beautify is ideal for:
- Projects that require specific, customized formatting rules
- Legacy JavaScript codebases
- Teams that want granular control over their formatting style
- Projects primarily focused on JavaScript, HTML, and CSS
- Environments where performance on large files is a concern
Uncrustify
Uncrustify is a highly configurable source code beautifier primarily designed for C-like languages.
Key Features
- Extreme configurability: Offers hundreds of options for precise formatting control
- C-family focus: Specializes in C, C++, C#, Objective-C, D, Java, Pawn, and VALA
- Token-based formatting: Works at the token level for fine-grained control
- Performance: Optimized for speed, even with large codebases
- IDE integration: Plugins available for various editors and IDEs
Here's an example of Uncrustify formatting C++ code:
Pros and Cons
Pros
- Unmatched configurability with hundreds of formatting options
- Excellent for C-family languages with specialized rules
- High performance even with large codebases
- Mature and stable with years of development
- Can precisely match existing coding standards
Cons
- Steep learning curve with complex configuration
- Limited language support outside C-family languages
- Configuration can be overwhelming and time-consuming
- Less intuitive setup compared to modern formatters
- Documentation can be technical and difficult to navigate
Best Use Cases
Uncrustify is ideal for:
- C, C++, C#, Java, and other C-family language projects
- Teams with very specific formatting requirements
- Large codebases where performance is critical
- Projects that need to match existing style guides precisely
- Environments where maximum control over formatting is desired
Head-to-Head Comparison
Let's compare these formatters across several key dimensions to help you make an informed choice.
Language Support
| Formatter | Supported Languages |
|---|---|
| Prettier | JavaScript, TypeScript, JSX, JSON, CSS, SCSS, HTML, Vue, Angular, Markdown, YAML, GraphQL |
| JS-Beautify | JavaScript, HTML, CSS |
| Uncrustify | C, C++, C#, Objective-C, D, Java, Pawn, VALA |
Configuration Options
| Formatter | Configuration Approach | Number of Options |
|---|---|---|
| Prettier | Opinionated with minimal options | ~10 core options |
| JS-Beautify | Moderately configurable | ~30-40 options |
| Uncrustify | Extremely configurable | 600+ options |
Performance
Performance can vary significantly depending on file size, language, and complexity:
- Prettier: Generally fast for most files, but can slow down with very large files or complex JSX
- JS-Beautify: Typically faster than Prettier, especially for large JavaScript files
- Uncrustify: Highly optimized for performance, often the fastest option for C-family languages
Ecosystem & Integration
| Formatter | IDE Support | CI Integration | Plugin Ecosystem |
|---|---|---|---|
| Prettier | Excellent (VS Code, WebStorm, etc.) | Excellent | Rich plugin ecosystem |
| JS-Beautify | Good | Good | Limited |
| Uncrustify | Moderate | Good | Limited |
Community & Support
- Prettier: Large, active community with frequent updates and extensive documentation
- JS-Beautify: Established community but less active development in recent years
- Uncrustify: Smaller but dedicated community, primarily focused on C-family languages
Decision Guide: Choosing the Right Formatter
To help you choose the right formatter for your needs, consider these questions:
-
What languages are you primarily working with?
- For JavaScript/TypeScript and web technologies: Prettier is likely your best choice
- For C, C++, C#, Java: Uncrustify offers the most specialized support
- For basic JS/HTML/CSS with specific formatting needs: JS-Beautify may be suitable
-
How much configuration control do you need?
- Minimal configuration, just want it to work: Prettier
- Moderate configuration needs: JS-Beautify
- Maximum control over every aspect: Uncrustify
-
What's your team's experience level?
- Teams new to formatting or with mixed experience: Prettier's simplicity is beneficial
- Teams with specific formatting preferences: JS-Beautify offers a good balance
- Teams with formatting experts or very specific requirements: Uncrustify's power may be worth the complexity
-
What's your project size and performance needs?
- For very large codebases where performance is critical: Uncrustify or JS-Beautify
- For most projects where convenience outweighs performance: Prettier
Conclusion
Each of these formatters has its strengths and ideal use cases:
- Prettier excels in modern web development with its opinionated approach and broad language support
- JS-Beautify offers a good balance of configurability and ease of use for JavaScript, HTML, and CSS
- Uncrustify provides unmatched control for C-family languages with its extensive configuration options
The "best" formatter ultimately depends on your specific needs, languages, and team preferences. Many projects even use multiple formatters for different languages or parts of their codebase.
Regardless of which formatter you choose, implementing automated code formatting in your workflow will improve code quality, reduce style debates, and help your team focus on what matters most: building great software.