HTML5 Validator

Find syntax or format errors in your HTML

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What this tool can

The HTML5 Validator tool helps you to find all syntax or format errors in your HTML source code.
  • Flexible data input
    You can enter the URL, download the html file or enter the text directly to perform the validation.
  • Show full and detailed errors
    All error messages and warning contents are displayed.
    Each notification message includes message type (error or warning) information, content, error location (line, column) and faulty source.
    You can use the group message function, to group similar errors into one group.
  • Convenient
    You can click on the link describing the location, to move to the corresponding source code. Also, in the source code, when hovering over the highlighted text, the message content is also displayed.
    When choosing to display images, you can filter images displayed by 3 options: image does not have alt attributes, image has alt attributes but does not have description, or images has alt attributes.

Useful for

  • Developers can review HTML source code quickly and gently.
  • When you want to check if the images in the HTML content are not displayed, the alt attribute is missing, or the alt content or the image name do not match the image content and fix them to optimize the search engines.

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