Overview
Feature flags let you toggle features on or off for specific users, groups, or percentages of traffic without redeploying code. They're the foundation for safe rollouts, A/B testing, and remote configuration.
Common use cases include:
- Phased rollouts — Ship to 5% of users, monitor, then gradually increase
- Kill switches — Instantly disable a broken feature without redeploying
- Targeting — Show features to specific users, teams, or organizations
- A/B testing — Run experiments with multivariate flags and track results
- Remote config — Send JSON payloads to configure behavior server-side
- Beta programs — Let users opt in to early access features
SDKs and frameworks
All the features you expect
Even better in the PostHog ecosystem
Experiments
Run A/B tests powered by feature flags with statistical significance tracking.
Session replay
Watch recordings of users interacting with flagged features to understand impact.
Product analytics
Track how flagged features affect conversion, retention, and revenue.
Error tracking
Roll back flagged features when they cause exceptions for users.
Surveys
Collect feedback from users who have specific feature flags enabled.
Data warehouse
Query flag evaluation data alongside product data with SQL.
Next steps
Questions? Ask PostHog AI.
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