GrowthBook
Open-source feature flags and A/B testing that query your existing data warehouse directly.
why this verdict
Keep paying — OpenAI has not replaced it
OpenAI's version overlaps, but does not finish the analytics job, so this one still earns its $20/mo.
- A named launch, not a vibe named, unlinked
- LLM-written statistical analysis reducing the perceived difficulty of running experiments. OpenAI, March 6, 2025 — no announcement link recorded yet.
- How much of the job it covers not the job editorial call
- Parts of it. The job still needs the tool to get finished.
- Is there a free way to do it? yes
- 2 of 3 listed replacements have a usable free tier: Statsig and PostHog.
- What the call is worth $240/yr
- $20/mo at the entry paid tier — $240 a year per seat.
- Threatened by
- OpenAI
- Since
- March 6, 2025
- List price
- $20/mo
- Per year
- $240
The backstory
GrowthBook runs experiments against the warehouse you already have, so metric definitions stay where your data lives. AI can explain a lift number, but it cannot substitute for correct randomisation, exposure tracking and flag delivery. Being open source and warehouse-native means teams adopt it for control rather than for a report. The pressure lands on the analysis layer, which was never the hard part.
Escape hatches
Hosted experimentation with a stronger stats engine
statsig.com open_in_newOpen-source flags and tests alongside analytics
posthog.com open_in_newEnterprise option when governance matters more than cost
optimizely.com open_in_new2 of 3 replacements have a usable free tier.