What Is a Toggle?

The word toggle is a synonym for switch, and can be used to describe any kind of on-off control. It’s commonly used in computing, and is the name for a switch with two positions, like the one that turns on Caps Lock or mute your video chat. It’s also a verb, meaning to alternate between two positions using a single switch or lever. For example, you can toggle a light between on and off by clicking it.

In product management, a toggle is a type of feature flag that can be enabled or disabled at runtime. It’s often used to enable new or experimental features for a small subset of users while still allowing existing functionality to continue to work for the majority of people. A toggle can be a great way to get user feedback or test hypothesis before rolling out a new feature.

A toggle can also be used to perform multivariate or A/B testing. By assigning a given user into different cohorts and at runtime directing them down one codepath or another using a toggle we can measure the aggregate behavior of different versions of the same feature. This technique is commonly used to improve things like a checkout flow or the Call To Action wording of an email signup button.

When designing a toggle, it’s important to use a clear label that explains what the control will do when activated. Ideally, it should also include a visual cue that shows what state the toggle is currently in, such as a contrasting color or movement. This ensures that users don’t accidentally activate the wrong option, or worse, change a setting they didn’t intend to.

Toggle labels should also be easy to understand, especially when used in combination with other controls. For example, a toggle label for a button that can turn a screen off should not be placed next to a checkbox or radio button. This can cause confusion if the toggle isn’t clearly labeled as an on/off control.

While a toggle can be an excellent tool for experimentation and optimization it’s critical to have a well-defined test plan for how a team will use them in production. Without a robust system for in-memory re-configuration it can be very difficult to test for regressions caused by a toggle being flipped on or off. To avoid this, many teams choose to make sure that the toggle configuration that they expect to see in production is tested at least once with all toggles flipped On. This helps ensure that any changes to existing or legacy behavior will be isolated and only impact a small percentage of the user base.