Toggle is a user interface element that allows users to update preferences, settings or other types of information. When used correctly, they help to keep users informed and improve user experience. When using toggles, it’s important to provide direct labels, use standard visual design and deliver immediate results. When used incorrectly, they can be confusing and obstruct user flow.

Toggles are typically implemented as buttons that have two opposing states (on and off) and users can select one of them by pressing it. They are commonly found in options menus and other similar places in software and hardware. For example, the Caps Lock and Num Lock keys on a keyboard are toggle switches that are initially off but once pressed they turn on.

WCAG recommends that designers don’t rely solely on colors to signal state change, which is often the case with toggle switches. Adding a clear label next to the toggle is also a good idea. However, it’s worth noting that a toggle switch that uses green to represent an on state may cause confusion for users who have red/green color blindness or other visual impairments.

Another way toggles can be useful is in the form of an experiment toggle, which is a component in a website or app that will consistently send a given user down one code path or another, depending on their cohort. This is a common technique for making data-driven optimizations. Toggles are generally short-lived, whereas experiment toggles tend to stick around for a longer period of time.