A toggle, or togle, is a switch that has two states: on and off. It’s a common part of software and hardware. In software, it’s used for options and preferences. On computers, it’s also used to activate features such as Caps Lock and Num Lock.

Toggles are a great way to update settings and preferences on your site or app. They help users see how changes will affect their experience and give them immediate results.

Labels and Visual Design

Toggle labels should be clear and direct. They should describe what the control will do when the switch is on, and they shouldn’t be neutral or ambiguous.

Color is an important visual signifier for toggles. Ensure that the colors you choose convey state change and contrast. This helps ensure that your toggles look like sliders and provide a consistent user experience across different devices.

Feature Flags and Toggle Configuration

The use of static files to manage toggle configuration can be relatively fiddly at certain scales. This can make it difficult to ensure consistency across a fleet of servers.

Some teams find that exposing an endpoint which allows for dynamic in-memory re-configuration of toggles can be useful. This can be a particularly useful tool for Experiment Toggles where it’s often necessary to exercise both paths of a toggle.

Some teams have a rule that toggles that are no longer required should be removed before they are added to production. Other teams put “expiration dates” on their toggles.