Feature toggle

Also called: feature flag, feature switch

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A feature toggle is the same thing as a feature flag: a switch that changes application behaviour at runtime without deploying new code. "Toggle" and "flag" are interchangeable — there is no technical difference between them.

Flag or toggle?

"Feature toggle" is the older term, popularised by trunk-based-development and continuous-delivery practitioners; "feature flag" spread later through SaaS vendors and is more common today. You will also see "feature switch" and "feature gate". The distinction that actually matters is not the word but the kind of toggle — release toggles (short-lived, for decoupling deploy from release), experiment toggles (A/B tests), ops toggles (kill switches), and permission toggles (tier gating) — a taxonomy that describes lifespan and purpose, not naming.

Does the name change anything in practice?

No. The workflow is identical whichever word your team uses: wrap functionality in a conditional, configure the value remotely, and change behaviour without touching code. The practical advice is to pick one term and stay consistent in your own codebase and documentation so searches and onboarding stay simple.

Want the full picture? Read the concept guide: What are feature flags? →

Related terms

Feature flag

A feature flag is a conditional in your code whose value is controlled from a remote dashboard, letting you turn functionality on or off without deploying new code.

Dark launch

A dark launch ships a feature to production turned off or invisible to users, so the code runs in the live environment before anyone sees it — you reveal it later on your own schedule.

Kill switch

A kill switch is a feature flag used to disable functionality instantly in production — flip it off and every SDK stops running the risky code path within seconds, no redeploy required.

Browse the full feature flag glossary →

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