What Is a Toggle?


In computer technology, a toggle is an on-off command. It is used to describe software options that allow users to turn on and off certain settings. For example, the Caps Lock key and Num Lock key are toggles.

A toggle is also the term used for the switch on a light bulb that switches between off and on. Often, these options are on or off for a particular preference and only require the user to click a button or press a combination of keys.

Visual Significance of Toggles

Color is an important visual signifier for toggles and should be used to signal state change. For example, a red switch can be counterintuitive for people who are unfamiliar with the concept of a toggle, so designers should use a high-contrast color or state descriptors like On and Off to make it clear what a switch is.

Managing Toggle Configuration

Many teams use static files to manage toggle configuration, which is an effective solution for simple cases, but becomes increasingly unwieldy as the number of feature flags grows. In response to this many organizations move toggle configuration into a centralized store, usually an existing application DB.

Savvy teams use a combination of static and dynamic toggle management to keep toggle inventory as low as possible. For example, some teams add a task on their backlog to remove a toggle when it is no longer needed, while others use a “time bomb” feature flag that will fail a test or refuse to start the app if a toggle is still around after its expiration date.