HTML Guide for non-space characters

Misplaced non-space characters inside a table.

The W3C HTML Validator issue “Misplaced non-space characters inside a table” usually occurs when there are text nodes (or other elements) that are not properly placed within table elements. In HTML, all text content should be contained within table cells.

How to Fix the Issue

To resolve this issue, ensure that all text content is placed inside <td> or <th> elements, which are the valid child elements of <table>, <tr>, and related elements. Here’s how you can identify and fix the issue:

Example of Incorrect Table Structure

<table>
  <tr>
<!-- This is misplaced content -->

    <td>First Cell</td>
    <td>Second Cell</td>
  </tr>
</table>

Corrected Table Structure

<table>
  <tr>
<!-- All text should be inside <td> or <th> -->

    <td>First Cell</td>
    <td>Second Cell</td>
  </tr>
</table>

Guidelines

Text Content: Ensure that all text (including any headers or titles) is wrapped in <td> (for data cells) or <th> (for header cells). Keep in mind that event the non-breaking space character ( ) counts as text.
Table Structure: Remember a typical structure for a table includes <table> containing one or more <tr> elements, which in turn contain the <td> or <th> elements.
No Direct Text Nodes: Avoid having any direct text nodes outside of the cell elements within the table.

Non-space characters found without seeing a doctype first. Expected “<!DOCTYPE html>”.

A missing or incorrectly placed <!DOCTYPE html> declaration at the very start of your HTML document causes this error.

The <!DOCTYPE html> declaration must be the very first thing in your HTML file, before any HTML code. This declaration tells the browser to use standards mode, ensuring reliable rendering. Without it, browsers may behave unpredictably or trigger quirks mode, and validators will issue an error.

Correct Example:

<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Valid HTML Document</title>
  </head>
  <body>
    <p>Hello, world!</p>
  </body>
</html>

Incorrect Example (doctype missing):

<html lang="en">
  <head>
    <title>Invalid HTML Document</title>
  </head>
  <body>
    <p>Hello, world!</p>
  </body>
</html>

Incorrect Example (doctype not at the very start):

Some misplaced text.

<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Invalid Placement</title>
  </head>
  <body>
    <p>Hello, world!</p>
  </body>
</html>

Always ensure <!DOCTYPE html> is the first line.