DevTools LogoDevTools

HTML Formatter/Validator

Format, validate, and minify HTML documents with accessibility warnings and structure analysis

Processing Mode
Input HTML
Paste your HTML code or upload a file
Formatted HTML
Pretty-printed with proper indentation
How to Use

Format Mode

Pretty-prints HTML with proper indentation, line breaks, and customizable formatting options for better readability.

Minify Mode

Removes all unnecessary whitespace, comments, and line breaks to reduce file size for production deployment.

Validate Mode

Analyzes HTML structure, checks for best practices, and provides detailed warnings about accessibility and markup issues.

Explore Other Categories

View All

Encoders & Decoders

Encode and decode various data formats

5 available

Generators

Generate various types of data

4 available

Security Tools

Security and cryptographic tools

2 available+1 coming soon

Converters

Convert between different formats and units

3 available+1 coming soon

Utilities

Helpful development utilities and tools

4 available+6 coming soon

Data Converters

Convert between different data formats

5 available+1 coming soon

More Formatters & Validators

View More

JSON Formatter/Validator

Format and validate JSON data

XML Formatter/Validator

Format and validate XML data

YAML Formatter/Validator

Format and validate YAML configuration files

CSS Formatter/Minifier

Format and minify CSS stylesheets

SQL Formatter

Format and beautify SQL queries

Popular Developer Tools

View More

Base64 Encoder/Decoder

Encode and decode Base64 strings online free

URL Encoder/Decoder

Encode and decode URL components safely

HTML Entity Encoder/Decoder

Encode and decode HTML entities

Binary Encoder/Decoder

Convert text to binary and binary to text

Hex Encoder/Decoder

Convert text to hexadecimal and back

UUID Generator

Generate UUID v1 and v4 unique identifiers

How to Use Free Online HTML Formatter and Validator Tool

Our free online HTML formatter provides instant HTML formatting, validation, and minification capabilities right in your browser. Simply paste your HTML code, choose your processing mode, and get immediate results. No signup required, completely secure, and works offline.

Key Features

  • Instant HTML formatting with proper indentation and structure
  • Complete HTML validation with detailed error messages
  • HTML minification for reduced file sizes
  • Document structure analysis and statistics
  • Accessibility and best practice warnings
  • Customizable formatting options and indentation
  • File upload support for large HTML documents
  • One-click copy results to clipboard
  • Download formatted or minified HTML files
  • Real-time processing as you type
  • Completely secure - all processing happens in your browser
  • No signup or registration required
  • Works offline after loading

Why Use This HTML Tool?

Perfect for web developers, frontend engineers, and designers who work with HTML markup. Save time debugging HTML files with our comprehensive formatting and validation features. Whether you're working with templates, email HTML, or web pages, our tool helps you quickly identify issues and improve code readability.

Frequently Asked Questions

Is this HTML formatter free to use?

Yes, our HTML formatter is completely free with no limitations, signup requirements, or hidden costs.

Is my HTML code secure?

Absolutely. All HTML processing happens locally in your browser using DOMParser API. No code is sent to servers.

What HTML formats are supported?

We support all HTML5 formats including complete documents, fragments, templates, and legacy HTML4 markup.

Does it work offline?

Yes, once the page loads, the HTML formatter works completely offline without internet connection.

Can I customize formatting options?

Yes, you can adjust indentation size, remove comments, sort attributes, and configure other formatting preferences.

What about accessibility validation?

Our tool provides basic accessibility warnings including missing alt attributes, title elements, and semantic markup recommendations.