Flagsmith Review 2026
Open Source Feature Flag Service
What is Flagsmith?
Flagsmith is an open-source feature flag service for developing, implementing, and managing feature flags across web, mobile, and server-side applications. It supports remote config, segmentation, A/B testing, and SaaS, private cloud, or on-prem deployment.
Best for
Mixed
Use cases
- Feature management
- Canary deployments
- A/B testing
Key features
Feature flags across platforms
Remote config
Granular segmentation
A/B and multivariate tests
Pricing
Model
freemium
Price range
Open source; Start Free Trial for hosted plans
Free tier
Yes
Integrations
Flagsmith integrates with 1 tools including:
REST API
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