Code Formatter
Beautify or minify your code. Supports JSON, HTML, and XML.
Features
- • Prettify: Add indentation and line breaks
- • Minify: Remove whitespace to reduce size
- • Validate: Check for syntax errors
- • Fast: Client-side processing
Use Cases
- • Format API responses
- • Minify production code
- • Debug malformed JSON
- • Clean up HTML/XML
Complete Guide to Code Formatting
Why Code Formatting Matters
Code formatting is more than aesthetics—it's a fundamental practice that impacts code quality, team collaboration, and maintainability. Consistently formatted code is easier to read, reduces cognitive load when reviewing changes, and helps catch bugs early.
In professional development environments, teams enforce formatting standards through automated tools like Prettier, ESLint, and language-specific formatters. Our online code formatter provides the same functionality without requiring any installation—perfect for quick formatting tasks, code reviews, or when working on a machine without your usual tools.
Whether you're debugging a malformed JSON response, cleaning up HTML for documentation, or preparing configuration files, proper formatting makes your code professional and production-ready.
Prettify vs. Minify: When to Use Each
Prettify (Beautify) transforms compact code into a readable format with proper indentation and line breaks. Use prettify when:
- Debugging API responses or error messages
- Reviewing code during development
- Creating documentation or tutorials
- Collaborating with team members
Minify removes all unnecessary whitespace to reduce file size. Use minify when:
- Deploying code to production
- Optimizing API payload sizes
- Improving website load times
- Reducing bandwidth for mobile users
Supported Formats & Use Cases
| Format | Common Uses | Typical Size Reduction | Validation |
|---|---|---|---|
| JSON | APIs, config files, data storage | 20-50% when minified | Full syntax validation |
| HTML | Web pages, email templates | 10-30% when minified | Structure formatting |
| XML | Config files, data exchange, sitemaps | 15-40% when minified | Structure formatting |
How to Use This Code Formatter
- Select your language from the dropdown menu (JSON, HTML, or XML).
- Paste your code into the input area, or click "Load Sample" to see an example.
- Click "Prettify" to format with indentation, or "Minify" to compress the code.
- Copy the result using the Copy button and use it in your project.
- If there's a syntax error, you'll see a helpful error message to guide you.
🔒 100% Client-Side Processing
Your code never leaves your browser. All formatting, minification, and validation happens locally using JavaScript. This makes our tool safe for proprietary code, sensitive configurations, and any data you don't want uploaded to external servers. Perfect for enterprise developers who need a quick formatting tool without security concerns.
JSON Formatting Best Practices
✅ Do This
- • Use double quotes for strings and keys
- • Use 2 or 4-space indentation consistently
- • Validate JSON before sending to APIs
- • Minify JSON for production payloads
- • Use meaningful key names
❌ Avoid This
- • Single quotes (invalid in JSON)
- • Trailing commas after last items
- • Comments (not supported in JSON)
- • Unquoted keys
- • Mixed indentation styles
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Frequently Asked Questions
What is code formatting and why is it important?
Code formatting is the process of organizing code with consistent indentation, spacing, and line breaks to improve readability. Well-formatted code is easier to understand, debug, maintain, and collaborate on. Most development teams enforce formatting standards through tools like Prettier, ESLint, or built-in IDE formatters. Our tool helps you quickly format code snippets without installing any software.
What is the difference between prettify and minify?
Prettify (or beautify) adds indentation, line breaks, and spacing to make code human-readable. Minify does the opposite—it removes all unnecessary whitespace, comments, and formatting to reduce file size. Prettify is ideal for development and debugging, while minify is used for production code to improve website loading speed and reduce bandwidth usage.
Why would I minify JSON, HTML, or XML?
Minification reduces file size by removing unnecessary characters without changing functionality. For JSON APIs, smaller payloads mean faster network transfers. For HTML/XML, minification can reduce page load times by 10-30%. This is especially important for mobile users and improves Core Web Vitals scores. Our minifier can reduce JSON size by 20-50% depending on original formatting.
Is this code formatter safe to use with sensitive data?
Yes, absolutely. This tool runs 100% in your browser using client-side JavaScript. Your code is never sent to any server, stored anywhere, or logged. You can verify this by checking your browser's network tab—no data is transmitted when you format code. This makes it safe for proprietary code, API keys (though you should avoid pasting real keys), and confidential data.
What JSON errors does this tool detect?
The JSON formatter validates syntax and will detect: missing or extra commas, unquoted keys, single quotes instead of double quotes, trailing commas (not allowed in JSON), unclosed brackets or braces, invalid escape sequences, and non-string keys. When an error is found, the tool displays the error message to help you identify and fix the issue.
Can I format other languages like JavaScript, CSS, or Python?
Currently, this tool supports JSON, HTML, and XML formatting. For JavaScript, CSS, TypeScript, Python, and other languages, we recommend tools like Prettier or Black (for Python). These languages have more complex syntax rules that require specialized parsers. We may add support for additional languages in future updates.
How does JSON formatting work technically?
JSON formatting uses JavaScript's built-in JSON.parse() to validate and parse the input, then JSON.stringify() with spacing parameters to output formatted JSON. For prettify, we use 2-space indentation (industry standard). For minify, we output with no spaces. This approach ensures the output is always valid JSON if the input was valid.
What's the maximum code size this tool can handle?
Since processing happens in your browser, the limit depends on your device's memory. Typically, you can format files up to 5-10MB without issues on modern devices. For very large files (100MB+), consider using command-line tools like jq for JSON or dedicated build tools. Our tool is optimized for quick formatting of API responses, config files, and code snippets.
The Importance of Code Formatting in Modern Development
In today's collaborative development environment, consistent code formatting is non-negotiable. Tools like Prettier have revolutionized how teams maintain code quality, but sometimes you need a quick online solution without project setup or configuration.
This code formatter is designed for developers who need fast, reliable formatting for JSON, HTML, and XML. Whether you're debugging an API response, preparing documentation, or cleaning up configuration files, our tool provides instant results with zero friction.
The privacy-first approach means you can safely format sensitive code—API configurations, environment variables, or proprietary logic—without worrying about data exposure. Combined with our other developer tools, DevToolVault provides a complete toolkit for modern web development.