HTML Checking for Large Sites
Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.
An <a>
element has been found in an invalid place within a <table>
element.
For example, the following code would cause this issue:
<table>
<tr>
<a href="#">link</a>
</tr>
</table>
Instead, the <a>
element should be inside a <td>
element, as a <tr>
can’t hold content directly:
<table>
<tr>
<td>
<a href="#">link</a>
</td>
</tr>
</table>
Related W3C validator issues
Table rows on the same <table> element must have the same number of columns, which comes determined by the first tr row.
For example, this table is wrong as the first row defines 2 columns, while the second row tries to use 4 columns:
<table>
<tr>
<td>Liza</td>
</tr>
<tr>
<td>Jimmy</td>
<td>14</td>
</tr>
</table>
A <table> contains a <tr> row that has less <td> columns than the column count established by the first row. Check the table to ensure all rows have the same number of columns.
For example, in the following table, the first <tr> row defines that it’s 2 columns wide, but the second <tr> row tries to use only 1 column:
<table>
<!-- This first row sets the table as 2 columns wide -->
<tr>
<td>First</td>
<td>Second</td>
</tr>
<!-- This second row has only 1 column -->
<tr>
<td>Wrong</td>
</tr>
</table>
A button element, or an element with the role=button attribute, is not allowed to be nested inside an <a> element.
An <a> element cannot contain a descendant element with the attribute tabindex.
25,000 HTML checks per month. Fully automated.
Save time using our automated web checker. Let our crawler check your web pages on the W3C Validator.
The <table> element does not accept a height attribute. Use CSS instead.
The href attribute of an <a> element contains an invalid character, that should be properly encoded as a URI percent-encoded character.
12,500 Accessibility and HTML checks per week. Fully automated.
Let our automated scanner check your large sites using Axe Core and W3C Validator.
The target attribute on <a> elements can’t be blank.
This attribute defines the browsing context for links, that is, where should the linked documents be opened. This was used extensively on the now deprecated <frame> element, so you could give the name of the frame to open the document in, but is now more used to force links to open in a separate tab or window using target="_blank". Another option is using a name, so the new browsing context can be referred to on subsequent clicks on links with the same target.
For example, this will force the links to open on a new tab:
<a href="https://example.com" target="_blank">will open a blank tab</a>
The href attribute on an a tag expects a valid URL, but only http:// was found.
<a> tags can be used to link to an email address using the mailto protocol in the href attribute. Ensure that there is no space in the email address.
<a href="mailto: liza@example.com">This is wrong as it contains an space</a>
<a href="mailto:liza@example.com">This is OK</a>
Space characters are not allowed in href attributes. Instead, they should be converted to %20. In this example, the first line is invalid and the second is valid:
<a href="https://example.com#some term">invalid</a>
<a href="https://example.com#some%20term">valid</a>
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.