WCAG 2.5.4 Motion Actuation

Success criterion 2.5.4 protects people who cannot move a device on purpose — for example because their phone or tablet is mounted on a wheelchair — and people with tremors who move it by accident. It is level A and part of EN 301 549 (clause 9.2.5.4).

What the criterion requires

Functionality that can be operated by device motion or user motion can also be operated by user interface components, and responding to the motion can be disabled to prevent accidental actuation, except when:

• Supported interface: the motion is used to operate functionality through an accessibility supported interface;
• Essential: the motion is essential for the function and doing so would invalidate the activity.

"Device motion" means shaking, tilting or moving the device (detected by sensors such as the accelerometer). "User motion" means gestures in front of a camera. Ordinary input — typing, tapping, using assistive technology — is not motion actuation.

Typical failures on an online shop

• "shake your phone to undo" or "shake to get a coupon" with no button for the same action;
• tilting the phone to browse product images or to rotate a 360° view, with no on-screen controls;
• a web AR or "try on" feature that only responds to moving the camera, with no button-based alternative to see the product;
• a motion-triggered feature that cannot be turned off and fires when a customer walks with their phone.

Most shops do not use device motion at all; then the criterion does not apply.

How to check it

Automated: there is no axe-core rule for this criterion. Motion handlers run only on a real device with sensors, so it needs a manual check.

By hand: on a phone, browse the main pages and the checkout while shaking and tilting the device. Note anything that reacts. Ask the developer or check theme and app settings for features using devicemotion or deviceorientation events. For each, find a button or control that does the same, and a setting to turn the motion response off.

How to fix it

• Provide a visible button for every motion-triggered action (Undo, Next image, Rotate).
• Add a setting to turn off motion response, and respect it on every page.
• Do not start motion features automatically; let the user opt in.
• Remove motion features that add little value.

Related criteria

• 2.5.1 Pointer Gestures — complex gestures need simple alternatives.
• 2.1.1 Keyboard — functions must also work from the keyboard.
• WCAG 2.2 checklist — all A and AA criteria in one list.

Frequently asked questions

What does WCAG 2.5.4 Motion Actuation require?

Anything that can be triggered by moving the device (shaking, tilting) or by user motion in front of a camera must also work with normal interface controls, and the user must be able to turn off the motion response.

Are there exceptions to 2.5.4?

Two: when the motion operates the function through an accessibility supported interface, and when the motion is essential and replacing it would invalidate the activity, such as a step counter.

Is a "shake to get a discount" feature allowed?

Only if the same discount can be claimed with a button and the shake response can be switched off, so a person whose device is mounted or who has tremors is neither excluded nor triggers it by accident.