Required form controls

Definition If user input is required for a form control the required or aria-required attribute must must used.
Purpose
  • Users benefit from information being informed if a input to a control is required for form submission or task completion.
Required Yes for HTML4 Legacy Techniques ruleset mapping
WCAG 2.0 Success Criteria

3.3.3 Error Suggestion (Level AA, Primary Success Criterion)

Rule Category Forms
Scope Element
Target Resources textarea and input[type="text"] elements, and ARIA textbox, gridcell and combobox widgets
  • select
  • textarea
Techniques
  • To identify a required form control, add the HTML5 required attribute to the standard form controls.
  • If compatibility with HTML4 standards or legacy browsers and assistve technologies, you can also use aria-required="true" to indicate a form control is required.
  • Use the required attribute (or the aria-required if used) as the CSS selector for visually styling the form control as required. This ensures that the visual state stays synchronized with the accessibility API state used by assistive technologies.
  • The only reason to support both required and aria-required on the same form control is to support legacy browsers and assistive technologies. This required extra care to make sure the two values do not conflict. If they do conflict the required attribute will override the aria-required property value.
Informational Links