What Is a Toggle?

A toggle is a switch that allows you to choose between two states (on and off). It’s often used in computers, but it’s also found on many other devices.

A toggle can be turned on and off by pushing or pulling on the knob. In computing, a toggle is the equivalent of a checkbox. A toggle can be manipulated in two ways: it can be pushed or pulled by a user or it can be clicked on and off by a script.

The word toggle comes from the Latin togl, meaning “to move.” The verb toggle means to change or alternate between two different states (for example, switching between video chat and text). The meaning of the word has evolved as a result of its use in linguistics and technology.

In software development, toggles are a common tool for changing feature settings and preferences. They allow you to quickly enable and disable functionality in a live environment without needing to re-deploy the code base. Toggles are useful for testability, allowing teams to evaluate the impact of changes before committing them to production.

Toggles are an important part of a good DevOps process. Toggle configuration is typically stored in static files, which are easy to manage at a small scale, but become cumbersome when the number of toggles grows. To overcome this challenge many teams opt to move toggle configuration into some form of centralized store, often an existing application DB. This approach can be accompanied by the build-out of an admin UI that allows system operators, testers and product managers to view and modify feature flags and their configuration.

In most cases it’s best to have a single toggle per page, but some exceptions may be justified depending on the context. Toggle switches should be designed with clear labels, so that users can clearly understand what the toggle is doing (whether it’s on or off). When a toggle is on it should always be active and visible to the user. It’s often easier to create a toggle that looks like a checkbox than it is to make one that looks logical and follows convention. Using toggles should be an intentional design decision.