GrowthBook
GrowthBook
Free feature flags & testing
GrowthBook is an open-source, warehouse-native platform for feature flags, experimentation, and product analytics. Self-host or use GrowthBook Cloud.
Feature flags: Boolean, string, number, and JSON values with targeting rules, percentage rollouts, instant kill switches, and stale flag detection.
Experimentation: A/B and multivariate tests across server-side, client-side, mobile, and edge, with Bayesian and frequentist engines.
Warehouse-native: Connect Snowflake, BigQuery, Redshift, Databricks, ClickHouse, Postgres, and more. Metrics are transparent SQL, and end-user PII stays in your warehouse.
AI-ready: An MCP server and agent skills let you manage flags and experiments from your editor.
24+ SDKs: JavaScript, React, Node.js, Python, Ruby, Go, PHP, Java, Swift, Kotlin, and more, plus a REST API, webhooks, and dbt sync.
Pricing is per seat. Start free with unlimited events, experiments, and traffic. Paid plans add advanced statistics, safe rollouts, SSO, and approval workflows.