GrowthBook
Open source feature flags and A/B testing platform
About GrowthBook
GrowthBook is an open-source platform for feature flagging and A/B testing that gives engineering and product teams full control over experimentation. It integrates with your existing data warehouse, supports advanced statistical methods (Bayesian, Frequentist, Sequential), and offers 24+ SDKs for seamless implementation across web and mobile.
Pros & Cons
Pros
- Open-source with self-hosting option for full data sovereignty
- Warehouse-native approach avoids data duplication and vendor lock-in
- Advanced statistical engines (Bayesian, Frequentist, Sequential) with CUPED support
- Generous free tier with unlimited flags and experiments
- Extensive SDK support across 24+ platforms and languages
- Y Combinator backed with strong community and documentation
Cons
- UI can be confusing for less technical team members
- Initial setup and integration requires engineering effort
- Visual editor and advanced features only available on Pro plan
- JSON payload configuration can be complex for newcomers
- Smaller ecosystem compared to established competitors like LaunchDarkly or Optimizely
Key Features
Feature Flags
Control application behavior remotely with boolean, number, string, and JSON flag types with advanced targeting rules
A/B Testing & Experimentation
Run unlimited A/B tests with support for Bayesian, Frequentist, and Sequential statistical engines
Visual Editor
Run A/B tests on your website without code changes using a no-code visual editor
Warehouse-Native Analytics
Connect directly to your data warehouse (BigQuery, Snowflake, Redshift, etc.) for experiment analysis without data duplication
Gradual Rollouts
Incrementally release features to a percentage of users and monitor impact before full deployment
CUPED Variance Reduction
Use CUPED and other advanced statistical techniques to detect smaller effects and run experiments faster
24+ SDKs
Native SDKs for React, Python, Go, Ruby, Android, iOS, Flutter, and many more platforms
Self-Hosting Option
Deploy the open-source edition on your own infrastructure for complete data control and privacy
Pricing
- Unlimited feature flags
- Unlimited experiments
- Up to 10M API requests/month
- Community support
- Self-host or cloud
- Everything in Starter
- Free for up to 3 users
- Visual editor
- Flag scheduling
- Advanced permissions
- Custom fields
- Priority support
- Everything in Pro
- Unlimited API requests
- SSO/SAML
- Audit logs
- SLA guarantees
- Dedicated support
- Custom integrations
Best For
Progressive Feature Rollouts
Gradually release new features to increasing percentages of users while monitoring metrics and rolling back instantly if issues arise
Product Experimentation
Run rigorous A/B tests on pricing pages, onboarding flows, and UI changes with warehouse-native statistical analysis
Engineering Release Management
Decouple code deployment from feature releases using feature flags, enabling trunk-based development and safer releases
Data-Driven Decision Making
Connect to your existing data warehouse to analyze experiment results alongside all your product analytics without moving data
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Featured In
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