---
sidebar_position: 21
keywords: [html, sample html, basic html]
---


# HTML Validation

Validating your HTML code ensures that it complies with the standards set by the World Wide Web Consortium (W3C). Valid code improves cross-browser compatibility, accessibility, and overall quality of your web pages.

## Online Validators

Several online tools are available for validating HTML code. These tools check your code against HTML standards and provide detailed error reports.

### W3C Markup Validation Service

The W3C Markup Validation Service is a widely used tool for validating HTML code. Simply enter the URL or upload the HTML file to validate your code.

[Visit W3C Markup Validation Service](https://validator.w3.org/)

### Validator.nu (HTML5 Validator)

Validator.nu is an HTML5 validator that checks your code against the latest HTML standards. It provides real-time validation as you type and supports custom validation profiles.

[Visit Validator.nu](https://validator.nu/)

## Browser Developer Tools

Most modern web browsers come with built-in developer tools that include HTML validation features. These tools can quickly identify syntax errors and other issues in your HTML code.

### Google Chrome Developer Tools

Google Chrome's Developer Tools include a built-in HTML validator. Simply right-click on a web page, select "Inspect", and navigate to the "Console" tab to view HTML validation errors.

### Mozilla Firefox Developer Tools

Mozilla Firefox's Developer Tools also include an HTML validator. Access it by right-clicking on a web page, selecting "Inspect Element", and navigating to the "Console" tab.

## Command-Line Tools

If you prefer working from the command line, you can use command-line HTML validators to validate your HTML code locally.

### HTML Tidy

HTML Tidy is a command-line tool that can clean up and validate HTML code. It checks for syntax errors, deprecated tags, and other issues in your HTML files.

[Download HTML Tidy](https://www.html-tidy.org/)

### Nu Html Checker (v.Nu)

v.Nu is a command-line HTML5 validator based on the Validator.nu service. It validates HTML files against the HTML5 specification and provides detailed error reports.

[Visit v.Nu GitHub Repository](https://github.com/validator/validator)

By regularly validating your HTML code using these tools, you can ensure that your web pages adhere to HTML standards and maintain high quality and compatibility across different browsers and devices.
