A toggle is a switch that has two states, either on or off. It’s used to control an action in a user interface and it can be triggered by clicking on it, or by the user clicking in some other way. A toggle is often found in a drop-down menu, a button or a progress bar and can be used to hide content from users or to show them more. Toggles are often used for A/B testing and can be changed remotely by the engineering team.

The word toggle comes from the Latin verb “to bind.” It describes a rod or pin that is placed transversely through an eye, loop or other opening in order to bind it temporarily to another chain, rope, etc. This type of hardware was once commonly used to attach shackles to ships, for example. The toggle is also used to bind chains to other parts of a ship or to attach pieces together, such as a flagpole or flag to the mast of a ship. A toggle may also refer to a button on clothing, such as a sports jersey, or a part of a machine, such as a pulley.

Using Toggles

When designing toggles, it’s important to remember the proximity principle (that is, the closer a feature is to a user, the more likely they are to click on it). For this reason, it is best to use toggles on pages where other types of form fields exist. Toggles should be used sparingly, and they should be clearly visible to the user with clear labels that describe their function. If you must use toggles in pages that require a submit button, it’s best to avoid them altogether and instead add a checkbox or other type of input element that will result in immediate results.

Another important consideration when designing toggles is that the user should be able to determine whether they are currently in the on state or the off state. For this, it’s helpful to use high-contrast colors to indicate the current state of the toggle. It’s also wise to evaluate the societal and cultural implications of the color choices, as certain colors can have a negative meaning for some groups of people. To ensure that your toggles are accessible to all users, it’s also a good idea to use visual cues like color changes or animations to signal the change in toggle state.

Feature Toggles

Using toggles to roll out and roll back features during code deployment is an effective way to minimize issues with new releases. By defaulting to disabled, toggles help support trunk-based development by eliminating the need for feature branches and simplifying merge and reconciliation in source code management tools. They also allow engineers to test and deploy new features to a subset of users before making them live for all users. This helps to reduce the amount of time spent debugging and resolving performance and stability issues in production environments.