Optimizely vs GrowthBook
Side-by-side from the Top 11 ranking of The 11 Best A/B Testing Tools. Last verified June 13, 2026.
The short answer
Optimizely ranks higher on Top 11 (#1 vs #11) for Growth teams running experiments. The enterprise standard for its powerful stats engine and full-stack experimentation features.
At a glance
| Optimizely | GrowthBook | |
|---|---|---|
| Top 11 rank | #1 / The 11 Best A/B Testing Tools | #11 / The 11 Best A/B Testing Tools |
| Score (out of 9.4) | 9.2 | 7.4 |
| Best for | Enterprise-scale experimentation | Open-source testing on your data warehouse |
| Pricing | $$$$$ (Custom enterprise plans) | $ (Free to custom) |
| HQ | New York, USA | San Francisco, USA |
| Founded | 2009 | 2020 |
Optimizely
The enterprise standard for its powerful stats engine and full-stack experimentation features.
www.optimizely.comGrowthBook
An open-source tool that runs on your data warehouse, giving you full data ownership.
www.growthbook.ioMethodology and scoring weights live at /methodology. No vendor pays for placement — see about.