Understanding Success Criterion 2.5.6: Concurrent Input Mechanisms

Success Criterion 2.5.6 Concurrent Input Mechanisms (Level AAA): Web content does not restrict use of input modalities available on a platform except where the restriction is essential, required to ensure the security of the content, or required to respect user settings.

Intent

The intent of this Success Criterion is to ensure that people can use and switch between different modes of input when interacting with web content. Users may employ a variety of input mechanisms when interacting with web content. These may be a combination of mechanisms such as a keyboard or keyboard-like interfaces and pointer devices like a mouse, stylus or touchscreen.

Even though a device may have a primary input mechanism, the user may choose to employ alternative input mechanisms when interacting with the device. For example, the primary mechanism for mobile phones and tablets is the touchscreen. The user of these devices may choose to use a paired mouse or external keyboard as an alternative to using the touchscreen.

Users should be able to switch input mechanisms at any point should the user determine that certain tasks and interactions are more easily accomplished by using an alternative input mechanism. Content must not limit the user's interaction to any particular input mechanism unless the restriction is essential, or is required to ensure the security of the content or to respect user settings.

Note: A touch-typing web application, which teaches users how to touch-type on a keyboard and/or measures their proficiency and speed, would be an example of an essential limitation to a particular input mechanism.

Benefits

Examples

Related Resources

Resources are for information purposes only, no endorsement implied.

Techniques

Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. However, it is not necessary to use these particular techniques. For information on using other techniques, see Understanding Techniques for WCAG Success Criteria, particularly the "Other Techniques" section.

Sufficient Techniques

  • Only using high-level, input-agnostic event handlers (focus, blur, click) in Javascript (operating systems/UAs fire these events for all input mechanisms).
  • Registering event handlers for keyboard/keyboard-like and pointer inputs simultaneously in Javascript (see Example 1 in Pointer Events Level 2)

Failures

The following are common mistakes that are considered failures of this Success Criterion by the WCAG Working Group.

  • Restricting event handlers based on the presence of a detected input mechanism.
  • Using CSS Media Queries Level 4 Interaction Media Features to determine what the UA deems to be the "primary" input mechanism and assuming no other input mechanisms are present/may be added/may be used.

Key Terms

essential

if removed, would fundamentally change the information or functionality of the content, and information and functionality cannot be achieved in another way that would conform