Optimizely vs GrowthBook
Feature checklists rarely decide anything. What decides it is the pricing metric, who has to write the tests, and which limitation you can live with.
Entry price
Quote on request
Quote onlyFrom $40 per seat/month (cloud Pro, up to 30 users and 3 projects)
Free tierWhat drives the bill
The metric that actually scales your invoice.
Enterprise annual contracts, commonly in the tens of thousands and up. Priced by traffic and modules.
Seat-based rather than usage-based, so cost tracks the number of people using the platform rather than your traffic — which is why it stays dramatically cheaper than the commercial platforms at scale, especially self-hosted.
Free tier
No free tier.
Self-hosted open source is free with unlimited users on 1 project; the cloud Starter tier is free for up to 3 users.
Open source
MIT (core)
Self-hostable
No-code authoring
Languages
Platforms
Fits teams
Adoption
Widely used
Optimizely · since 2010
Widely used
GrowthBook · since 2021
Strengths
- 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.
- Warehouse-native by design — no duplicate event pipeline and no data leaving your control.
- Self-hosting removes per-user-volume pricing entirely.
- Both Bayesian and frequentist engines with sequential testing support.
Limitations
- 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.
- Requires a working data warehouse and someone who can define metrics in SQL.
- Self-hosting is operational work you own.
- Less polished governance and approval tooling than LaunchDarkly.
Best for
Large marketing organisations running continuous experimentation on high-traffic sites.
Data-mature teams that already have a warehouse and want to avoid volume-based pricing.
All of these integrate with: Segment, Snowflake, Slack.
Pricing last reviewed August 2026 and is indicative only — confirm on each vendor’s own page.