Understanding SC 2.5.5:Target Size (Enhanced) (Level AAA)

In Brief

Goal

Controls can be operated more easily, especially on touch screens.

What to do

Make custom targets at least 44 by 44 pixels.

Why it's important

Some people cannot tap small objects.

Intent

The intent of this success criterion is to help users who may have trouble activating a small target because of hand tremors, limited dexterity or other reasons. If the target is too small, it may be difficult to aim at the target. Mice and similar pointing devices can be hard to use for these users, and a larger target will help them greatly in having positive outcomes on the web page.

Touch is particularly problematic as it is an input mechanism with coarse precision. Users lack the same level of fine control as on inputs such as a mouse or stylus. A finger is larger than a mouse pointer, and generally obstructs the user's view of the precise location on the screen that is being touched/activated.

The issue can be further complicated for responsive/mobile sites which need to accommodate different types of fine and coarse inputs (e.g. a site that can be accessed both on a traditional desktop/laptop with a mouse, as well as on a tablet or mobile phone with a touch screen).

While this criterion defines a minimum target size, it is recommended that larger sizes are used to reduce the possibility of unintentional actions. This is particularly relevant if any of the following are true:

• the control is used frequently;
• the result of the interaction cannot be easily undone;
• the control is positioned where it will be difficult to reach, or is near the edge of the screen;
• the control is part of a sequential task.

Benefits

• Users who use a mobile device where touch screen is the primary mode of interaction
• Users with mobility impairments, such as hand tremors
• Users who find fine motor movements difficult
• Users who access a device using one hand
• Users with large fingers, or who are operating the device with only a part of their finger or knuckle
• Users who have low vision may better see the target

Examples

• Example 1: Buttons
  Three buttons are on-screen and the target area of each button is 44 by 44 CSS pixels.

Related Resources

Resources are for information purposes only, no endorsement implied.

• Apple touch target size recommendations
• Windows UWP Guidelines for touch targets
• Google Material Design Touch targets
• web.dev Accessible tap targets
• Human Fingertips to Investigate the Mechanics of Tactile Sense (PDF)
• One-Handed Thumb Use on Small Touchscreen Devices

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.

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.