About This HTML Issue
The <table> element in HTML supports a limited set of attributes — primarily global attributes like class, id, and style. The height attribute was never part of the HTML standard for tables (unlike width, which was valid in HTML 4 but has since been deprecated). Despite this, many browsers historically accepted height on <table> as a non-standard extension, which led to its widespread but incorrect use.
Because height is not a recognized attribute on <table>, using it means your markup is invalid and may behave inconsistently across browsers. Some browsers might honor it, others might ignore it entirely, and future browser versions could change their behavior at any time. Relying on non-standard attributes makes your code fragile and harder to maintain.
The fix is straightforward: remove the height attribute from the <table> element and use CSS to set the desired height. You can apply the CSS inline via the style attribute, or better yet, use an external or internal stylesheet with a class or ID selector.
Examples
❌ Invalid: height attribute on <table>
<table height="300">
<tr>
<td>Name</td>
<td>Score</td>
</tr>
<tr>
<td>Alice</td>
<td>95</td>
</tr>
</table>This triggers the validator error: Attribute “height” not allowed on element “table” at this point.
✅ Fixed: Using inline CSS
<table style="height: 300px;">
<tr>
<td>Name</td>
<td>Score</td>
</tr>
<tr>
<td>Alice</td>
<td>95</td>
</tr>
</table>✅ Fixed: Using a CSS class (preferred)
<style>
.tall-table {
height: 300px;
}
</style>
<table class="tall-table">
<tr>
<td>Name</td>
<td>Score</td>
</tr>
<tr>
<td>Alice</td>
<td>95</td>
</tr>
</table>
Using a class keeps your HTML clean and makes it easy to adjust the styling later without touching the markup. Note that min-height is often a better choice than height for tables, since table content can naturally grow beyond a fixed height, and min-height ensures the table is at least a certain size without clipping content.
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