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The value specified for a width attribute in CSS is not valid.
The width CSS property sets an element’s width. There are many allowed values for this attribute, for example:
/* <length> values */
width: 300px;
width: 25em;
/* <percentage> value */
width: 75%;
/* Keyword values */
width: max-content;
width: min-content;
width: fit-content(20em);
width: auto;
/* Global values */
width: inherit;
width: initial;
width: revert;
width: unset;Learn more:
Related W3C validator issues
Both <table> and <td> elements no longer accept a width attribute. Instead, you should use CSS as in this example:
<table style="width:100%;">
<tr>
<td style="width:50px;">Name</td>
</tr>
</table>The <table> element does not accept a height attribute. Use CSS instead.
The width and height attributes on <img> elements expect a digit to specify the dimension in pixels. It should not contain units, letters or percent signs.
You can achieve this using CSS instead, for example:
<!-- Invalid syntax, the height attribute expects only digits -->
<img src="photo.jpg" alt="cat" height="auto" />
<!-- Valid syntax using CSS -->
<img src="photo.jpg" alt="cat" style="height: auto" />The sizes attribute is used to complement the srcset attribute on an <img> tag for responsive images. When this attribute is present, all image candidates must specify its width.
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The attributes width and height of <img> elements expect a non-negative integer, so an empty string is not allowed. Either define the correct dimension, or remove this attribute.
The sizes attribute is used to complement the srcset attribute on an <img> tag for responsive images. When this attribute is present, all image candidates must specify its width.
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The attributes width and height on <img> elements define the dimensions of the image in CSS pixels, and expect a non-negative integer.
The <iframe> element, used to embed another document inside the current document, accepts both attributes width and height which must be valid non-negative integers. Percentages are not allowed for these attributes.
<img> elements accept a width attribute to specify the size in pixels. This value can only be an integer, it should not contain units or %. If you need to specify a percentage width, you can do that with CSS:
<img src="photo.jpg" alt="red car" style="width:100%;">The width and height attributes on <img> and <iframe> elements expect a digit to indicate the number of pixels. Ensure that this attribute contains only digits.
For example:
<!-- This is invalid because width is not a digit -->
<img width="225px" height="100px" alt="cat" src="cat.jpg" />
<!-- This is valid -->
<img width="225" height="100" alt="cat" src="cat.jpg" />Still checking your large sites one page at a time?
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