HTML Checking for Large Sites
Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.
The <font> element, used to define the font face, size and color in previous versions of HTML, is no longer valid in HTML5. Instead, you should rely on CSS styles.
For example, you can define a font size of 12px, bold text with inline styles like this:
<p style="font-size: 12px; font-weight: bold;">some text</p>Learn more:
Related W3C validator issues
The <big> tag is now obsolete. It was used to increase the size of text, you can do that using CSS instead. For example:
<p>Now this is <span style="font-size: larger;">big</span></p>The <tt> tag, used in HTML4 to apply a monospaced (fixed width) font to the text, was deprecated in HTML5. Instead, you should use CSS to apply the desired font.
Example, instead of this deprecated code:
<tt>This is deprecated</tt>You can define a monospaced text using font-family:
<span style="font-family: monospace;">This is monospaced text</span>The <table> element does not accept a height attribute. Use CSS instead.
A CSS definition for background-image could not be understood by the parser. Check its definition to ensure that it’s well formed and that it contains an appropriate value.
6,250 HTML checks per week. Fully automated.
Save time using our automated web checker. Let our crawler check your web pages on the W3C Validator.
The value on the display property is not valid.
The display CSS property sets whether an element is treated as a block or inline element and the layout used for its children, such as flow layout, grid or flex.
The specified CSS filter is not a standard one, and may only work in some browsers.
Still checking your large sites one page at a time?
Save time using our automated web checker. Let our crawler check your web pages on the W3C Validator.
font-display isn’t a CSS property, it’s a descriptor for use with the @font-face at-rule.
The value passed to the font-size property is invalid, probably missing the amount of px.
The font-size CSS property sets the size of the font, and this size can be expressed in different units, like em, % or px.
Example:
<!DOCTYPE html>
<html>
<head>
<title>Font-size Example</title>
<style>
p {
font-size: 16px;
}
</style>
</head>
<body>
<p>This is an example of a paragraph with a font-size of 16px.</p>
</body>
</html>This issue is a false positive by the W3C validator, fixed in the latest versions of Nu Validator.
The value revert is indeed a valid value for the CSS property font-size.
The @import CSS rule can be used to import a style sheet into another style sheet. It must appear at the top of the document, and after any @charset declaration.
6,250 HTML checks per week. Fully automated.
Save time using our automated web checker. Let our crawler check your web pages on the W3C Validator.