Should I Use HTML `img` Tag Attributes or CSS to Specify Image Dimensions for Optimal Performance?

Optimizing Image Display in HTML: Specify Height and Width Attributes or Not?

When displaying images with the HTML tag, it is essential to consider the most efficient approach for specifying their dimensions. Should you rely solely on CSS, include attributes within the tag, or employ a combination of both?

Options:

1. Using Attributes within the Tag:

<img src="profilepic.jpg" height="64" width="64" />

2. Using Style Attributes within the Tag:

<img src="profilepic.jpg" height="64" width="64">

3. Using CSS Styles Only:

<img src="profilepic.jpg">

Recommended Approach:

As per Google Page Speed, it is recommended to define the height and width directly within the tag. This allows the browser to determine the dimensions immediately, preventing unnecessary reflowing and repainting upon image download.

Validation Considerations:

Note that setting the dimensions via style attributes within the tag is not considered valid HTML by validators. To maintain validity, you should utilize an external CSS file or embed the CSS styles inline within a