JavaScript Beautifier

Format and beautify your JavaScript code with proper indentation and structure

Original JavaScript

Click to upload JavaScript file or drag and drop

Formatting Options:

Beautified JavaScript

Batch JavaScript Processing

Batch processing results will appear here...

JavaScript Formatting Best Practices

Code Style Guidelines

Use consistent indentation (2 or 4 spaces)
Add spaces around operators and after commas
Use meaningful variable and function names
Keep line length reasonable (80-120 chars)
Group related code with blank lines

Development Benefits

Improved Readability
Easier to understand code structure and flow
Better Debugging
Faster identification of errors and issues
Team Consistency
Uniform code style across developers

Features

  • 🎨 Advanced JavaScript formatting and beautification
  • 📂 File upload and batch processing support
  • ⚙️ Customizable indentation and spacing options
  • 📊 Detailed formatting statistics
  • 🔧 Operator spacing and brace positioning
  • 📋 One-click copy and download functionality

Use Cases

  • 🔧 Format minified JavaScript files
  • 📝 Improve code readability for development
  • 👥 Standardize team coding styles
  • 🔍 Debug and maintain existing scripts
  • 📦 Prepare JavaScript for version control
  • 🎯 Educational purposes and code review

Example algorithm (days)

// Using date objects in most languages:
days = (date2 - date1).days
Example: Days between 2025-01-01 and 2025-03-01 = 59 days (non-leap year).

6. Days Until

What it does: "Days Until" calculates how many days remain until a target date (a birthday, holiday, event). It is essentially a date-difference from today to a future date but often presented with friendly copy and optional recurrence handling for yearly events.

Features

Example: Today is 2025-09-24 — Days until 2025-12-25 (Christmas) = 92 days.

Putting it all together — Building reliable web calculators

Here are practical tips for developers and product managers building these tools on websites and mobile apps:

Sample HTML form (simplified)

<form id="percentage-form">
<label>Base: <input name="base" type="number" step="any" /></label>
<label>Percentage: <input name="percent" type="number" step="any" /></label>
<button type="submit">Calculate</button>
</form>

Attach client-side JS to compute results instantly and show them inside an accessible result container.

Design & SEO considerations

These calculator pages are highly searchable. Follow these quick SEO tips:

Conclusion

Age, Percentage, Loan, BMI, Date Difference, and Days Until calculators are simple but powerful tools that deliver immediate value. When implemented carefully — with correct formulas, clear UX, accessibility, and privacy considerations — they can significantly improve user engagement and trust. Developers should prefer reliable libraries for date and numeric handling, clearly document assumptions, and provide helpful explanations so users can understand and act on their results.

If you’d like, I can also provide ready-to-use JavaScript snippets for any of the calculators above (for example, a full amortization table script for the Loan Calculator or a BMI widget with unit toggles). Tell me which one you want first and I’ll include a copy-pasteable implementation.

Written as a detailed guide for developers and product teams building small utility calculators for web and mobile. Updated: 2025-09-24.