Toggle is a user-interface component that allows users to update preferences, settings, and other types of information. When implemented well, toggles provide clear results and make the experience simple and fast for users. They should be used to indicate mutually exclusive states and always offer direct labels and standard visual design. Toggles are typically best used to control elements that are visible on the page, such as article sections (title, subheading, and credits) or vignettes. They should also be used sparingly to control other kinds of form fields, such as long forms or checkboxes, where the need to save or confirm changes is unavoidable.

The configuration of a toggle can range from a simple “if” statement to complex decision trees, acting upon a variety of conditions. These could be fitness test results from other features in the codebase, a setting in feature management software or a variable provided by a config file.

Using toggles allows product teams to validate features with a small segment of users before rolling them out to the full user base. This can help reduce the risk of releasing features that flop and save time debugging when they do.

Toggles are a tool to enable rapid development and continuous deployment. They allow developers to roll out or back features in a fraction of the time needed to merge and reconcile a change to the master codebase. This is particularly valuable for teams that practice trunk-based development and want to shorten their release cycles.