The HTML <textarea> cols attribute, which specifies the visible width of the text area in average character widths, has broad and long-standing browser support.

This wide support means the cols attribute is a reliable way to define the initial visual width of a <textarea> element across virtually all modern and many older web browsers. While CSS can also be used to control the width, the cols attribute provides a fundamental sizing hint, especially for scenarios where CSS might be disabled or overridden.