Statsig vs Optimizely

Free tier available

Quote on request

One of the most generous free tiers in developer tooling; paid usage is billed on analytics events, not seats.

Enterprise annual contracts, commonly in the tens of thousands and up. Priced by traffic and modules.

Generous free tier including unlimited feature flags and a large monthly event allowance.

No free tier.

Widely used

Statsig (Amplitude) · since 2020

Widely used

Optimizely · since 2010

• Statistics engine is genuinely strong — sequential testing and CUPED are not marketing veneer.
• Flags, experiments and analytics in one system removes a whole class of integration work.
• Warehouse-native mode satisfies data-governance requirements.

• The most capable visual editor for non-technical experiment authoring.
• Deep personalisation and audience-targeting features.
• Established statistics with sequential testing, so peeking is handled correctly.

• Event-based pricing can escalate sharply on high-volume products.
• Broad surface area means a real learning curve.
• Changed hands twice in under a year — OpenAI acqui-hired the founding team in September 2025, and Amplitude took over the product and brand in May 2026, so the roadmap is still settling.

• Expensive, with a suite-oriented sales motion that pushes adjacent products.
• Client-side testing causes flicker and is increasingly blocked by browsers and blockers.
• Heavyweight for teams that only need a handful of experiments.

Product teams that want experimentation and analytics to share one source of truth.

Large marketing organisations running continuous experimentation on high-traffic sites.