VWO is $199/mo and Optimizely is talk-to-sales — both meter your traffic and keep your results in their cloud. Splitpoint defines experiments, assigns visitors with a tiny SDK and reads significance with a proper two-proportion z-test, all on your own server. $49, once.

• Experiments — Control plus N variants, weighted traffic split, holdout percentage, and URL/device targeting.
• Goals two ways — A JS track() call, or automatic conversion when a visitor hits a matching pageview URL.
• Tiny SDK — Vanilla JS under 3KB, no dependencies, never touches the DOM; assignments stick via deterministic hashing and localStorage so there is no flicker.
• React hook wrapper — An included hook for wiring code-level tests directly into your components.
• Results that mean something — Visitors, conversions and CR per variant with 95% CI, relative lift, a z-test p-value and a declare-winner workflow.
• Feature-flag mode — Boolean flags with percentage rollout on the same deterministic hashing, for gradual releases with zero extra setup.
• Mutual exclusion groups — Experiments sharing a group never run on the same visitor, so overlapping tests do not contaminate each other.

Runs as a Windows desktop app or on any $5 VPS (Docker included).

What’s included:

• Full source code (MIT): https://github.com/bensblueprints/ab-testing-tool
• Lifetime v1 updates
• Setup guide (README quick start)