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Shaishav Patel
Shaishav Patel

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How to Format and Beautify HTML, CSS, and JavaScript Online for Free — Paste, Beautify, Done

#javascript #webdev #html #css

You copy a JavaScript file from a vendor, open it in your editor, and it looks like this:

function a(b,c){var d=b*c/(b+c);return d.toFixed(2)}function calculateEMI(principal,rate,months){var r=rate/12/100;return principal*r*Math.pow(1+r,months)/(Math.pow(1+r,months)-1)}
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Two functions. No line breaks. No indentation. And you need to understand what it does.

This is where a code beautifier saves you.

What a code beautifier does

A code beautifier (also called a code formatter or prettifier) takes compressed or poorly structured code and rewrites it with:

  • Proper indentation
  • Line breaks after each statement
  • Consistent spacing around operators and braces
  • Readable block structure

It doesn't change logic, rename variables, or fix bugs — it only changes whitespace and formatting. The output runs identically to the input.

When you actually need one

  • Debugging minified vendor code — npm packages ship minified; beautifying lets you read stack traces and follow execution flow
  • Reading copy-pasted snippets — code from old docs or Stack Overflow often has mixed or broken indentation
  • Reformatting AI-generated code — ChatGPT and Copilot sometimes output inconsistent 2-space/4-space mixes
  • Before code review — paste messy code, format it, then share with your team
  • CSS from design tools — Figma and similar tools export compressed single-line CSS

How to format HTML, CSS, or JavaScript for free

Open the Code Beautifier — no login, no signup, no file upload.

Step 1: Select your language

Click the HTML, CSS, or JavaScript tab at the top. The formatter applies different rules per language — HTML preserves tag nesting, CSS groups properties per selector, JavaScript handles functions and blocks independently.

Step 2: Paste your code

Paste into the input area. It handles any size — minified bundle files, one-liner CSS resets, or compressed HTML templates.

Step 3: Choose indentation

Toggle between 2 spaces and 4 spaces:

  • 2 spaces: standard in React, Vue, Next.js, and most modern JS projects
  • 4 spaces: common in PHP, Python, and older Java codebases

Step 4: Click Beautify

The formatted code appears in the output panel instantly.

Step 5: Copy

Click Copy to copy the result to your clipboard.

HTML formatting

The HTML formatter:

  • Indents nested tags correctly
  • Preserves inline elements like <span> inside <p>
  • Doesn't modify content inside <pre>, <script>, or <style> blocks

Before:

<div class="card"><h2>Title</h2><p>This is a paragraph with <strong>bold text</strong> inside it.</p><ul><li>Item 1</li><li>Item 2</li></ul></div>
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After:

<div class="card">
  <h2>Title</h2>
  <p>This is a paragraph with <strong>bold text</strong> inside it.</p>
  <ul>
    <li>Item 1</li>
    <li>Item 2</li>
  </ul>
</div>
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CSS formatting

The CSS formatter puts one property per line with consistent spacing:

Before:

.card{background:#fff;border-radius:8px;padding:16px;margin-bottom:12px;box-shadow:0 2px 4px rgba(0,0,0,.1)}
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After:

.card {
  background: #fff;
  border-radius: 8px;
  padding: 16px;
  margin-bottom: 12px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, .1);
}
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JavaScript formatting

The JavaScript formatter handles function declarations, arrow functions, nested callbacks, object literals, and ternary operators.

Before:

const calculateEMI=(principal,rate,months)=>{const r=rate/12/100;return(principal*r*Math.pow(1+r,months))/(Math.pow(1+r,months)-1);}
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After:

const calculateEMI = (principal, rate, months) => {
  const r = rate / 12 / 100;
  return (principal * r * Math.pow(1 + r, months)) / (Math.pow(1 + r, months) - 1);
};
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2 spaces vs 4 spaces — which should you use?

Both are valid. The output is functionally identical.

  • Use 2 spaces if you're on a React, Vue, or Next.js project, or your prettier config defaults to 2 spaces
  • Use 4 spaces if you're reading PHP, Python, or Java, or if your team's .editorconfig specifies 4

When in doubt, match whatever the rest of the file uses.

Does it send my code anywhere?

No. The free online code beautifier runs entirely in your browser using the open-source js-beautify library. Your code never leaves your machine — there's no server, no upload, and nothing stored.

This matters when you're formatting internal code you can't share externally.

The full tool is live at Code Beautifier — supports HTML, CSS, and JavaScript, 2 or 4 space indent, no login required.

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