Code Formatters & ValidatorsFree Tool

HTML Validator

Provided byFreeFormatterfreeformatter.com

Validates HTML for well-formedness and W3C compliance, reporting structural and accessibility issues.

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About this tool

What HTML Validator does

HTML Validator is a free online tool that checks submitted HTML code for well-formedness and W3C compliance. It analyzes the syntax to identify structural errors such as unclosed tags or improperly nested elements, and it reports on potential accessibility gaps within the document structure. Users receive detailed reports highlighting errors and suggesting corrections, which aids in maintaining technical integrity and adhering to web standards during website development.

Step by step

How to use the FreeFormatter HTML Validator

  1. 1

    Open the HTML Validator page on FreeFormatter.com

  2. 2

    Paste your HTML code into the large input field or upload an HTML file

  3. 3

    Click the 'Validate' button to begin the analysis

  4. 4

    Review the generated report which lists errors and accessibility issues

  5. 5

    Apply the suggested corrections to improve your code's validity

Is it right for you

Best for

Developers and web designers who need to quickly validate HTML structure and check for W3C compliance during the website development lifecycle.

Limitations

  • Results are estimates and may not catch every edge case
  • The tool focuses on structural and accessibility issues rather than full visual rendering
  • No option to switch between different HTML validation standards or DTDs
Questions

HTML Validator FAQ

What types of errors does the HTML Validator typically catch?
The tool identifies common structural errors such as unclosed tags, improperly nested elements, and other syntax deviations from W3C best practices. It also highlights potential accessibility gaps within the HTML structure.
Can I validate HTML files I have saved on my computer?
Yes, the tool allows users to upload an HTML file directly from their local system for validation, in addition to pasting code into the input field.
Is the HTML Validator free to use, or are there limitations?
The HTML Validator on FreeFormatter.com is a free online tool. Users can validate their code without cost, receiving detailed reports on structural integrity and compliance with web standards.
How detailed are the validation reports produced by this tool?
The reports provide detailed feedback highlighting specific errors and suggesting corrections, focusing on both technical malformation and potential accessibility issues within the document structure.
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