Toggle is a switch that allows people to manage the state of a setting, view or piece of content. It’s commonly used to represent on/off commands, but can also be found in other types of controls like radio buttons or checkboxes. It’s best used when the surrounding context clearly identifies what the toggle affects. If there’s no contextual cue, consider using another control type, or adding a label next to the toggle.

Toggles are typically used in a blue area of the release cycle, and they should not stick around for more than a week or two, depending on how critical the functionality is to the product. They should be removed as soon as the feature is declared stable. Leaving release toggles in place longer than that will cause code maintenance headaches.

When designing a toggle, be sure to use high-contrast colors for states that differ from the default, and don’t rely solely on color to convey meaning. In addition, consider societal and cultural contexts, and whether a toggle is appropriate given the audience’s understanding of what it means to be in or out of a specific state.

Toggles can also be useful for A/B testing by creating cohorts of users and consistently sending them down one or the other code path based on which cohort they’re in. This can be done by creating a toggle that uses a switch to identify a cohort, and then a regular toggle to send them down that path.