Split vs Optimizely

Free tier available

Quote on request

Paid tiers are quote-based, priced by monthly tracked keys.

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

Free tier with limited monthly tracked keys.

No free tier.

Established

Harness · since 2015

Widely used

Optimizely · since 2010

• Automatic metric impact on every flag catches regressions nobody thought to measure.
• Guardrail alerts stop a bad rollout before it reaches everyone.
• Strong data-platform integrations.

• 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.

• Post-acquisition roadmap now sits inside Harness's broader platform strategy.
• Requires meaningful event instrumentation before the impact analysis is useful.
• Opaque enterprise pricing.

• 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.

Teams that want every release measured, not just deliberate experiments.

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