Feature flags & experimentation, in detail
Decoupling deploy from release is cheap; the pricing models are anything but uniform — per-seat, per-MAU, per-event and per-request all coexist here. That makes free-tier shape the deciding factor for most teams, and self-hostable open cores the escape hatch. Statsig's OpenAI acquisition (Sept 2025) added vendor-risk to the calculus.
| Tool | Free tier | Entry price | Billing unit | Watch out for | Best for |
|---|---|---|---|---|---|
| Statsig | Unlimited flag checks + 2M events/mo | Pro $150/mo flat | Per event above bundle | OpenAI-owned since Sep 2025 — roadmap risk to weigh | Flags + analytics + experiments, flat and cheap |
| PostHog | 1M flag requests + 1M events/mo | Usage-based | Per request/event, no seats | Many products, many meters — read the bill page | Flags bundled with product analytics + replay |
| LaunchDarkly | Developer plan (unlimited seats) | Foundation usage-based | Per connection / per 1k MAU | Historically opaque pricing; repackaged 2023–25 | Enterprise governance: approvals, RBAC, audit |
| GrowthBook | 3 seats cloud; unlimited self-host (MIT) | Pro $20/seat/mo | Per seat | Warehouse-native — you bring the data infra | A/B testing without per-evaluation billing |
| Flagsmith | 50k requests/mo | Start-Up ~$45/mo | Per request | Request-metered — high-traffic SDK config matters | Simple request pricing + on-prem option |
| Unleash | OSS core self-hosted | Paid cloud plans | Per seat (cloud) | Feature gap between OSS and paid editions | Self-hosted flags with an open core |
| ConfigCat | Free tier (limited configs) | Flat plans | Flat, by config/user volume | Lighter feature set — flags, not experimentation | Dead-simple flags with predictable flat pricing |
Pricing models and free tiers change often — check each vendor for current terms. Compiled July 2026; the most volatile figures verified on official pricing pages.
Official pages: Statsig · PostHog · LaunchDarkly · GrowthBook · Flagsmith · Unleash · ConfigCat
Entry price at a glance
Cheapest paid plan, USD per month — per-user plans shown for a single seat. Hatched bars are usage-based or quote-only; values marked ~ are approximate.
Notes & recent changes
- Statsig's free tier is the category outlier: unlimited flag checks at any scale, unlimited seats, 2M analytics events — verified July 2026.
- PostHog has cut prices repeatedly ('prices only go down') and charges nothing per seat; cost scales purely with usage.
- LaunchDarkly sells governance (approvals, audit, RBAC) more than flags — evaluate it against compliance needs, not feature lists.
Which one should you pick?
- Startup wanting flags + experiments free → Statsig.
- Already using PostHog analytics → its flags are one bill away.
- Enterprise change-management requirements → LaunchDarkly.
- Must self-host → GrowthBook, Unleash or Flagsmith.