Comparison
This page compares ProveBetter with Optimizely honestly: what Optimizely does well, where ProveBetter is deliberately different, and which teams should still pick Optimizely. The short version — if you want to know the price before a sales call, run client-side and server-side tests in one platform, and read results in plain language, ProveBetter is built for you. If you need a visual editor at enterprise scale, Optimizely is a legitimate choice, and this page says so outright.
Optimizely is the enterprise incumbent in web experimentation, and its strengths are real. It is organized — publicly and by design — as two products:
The two products are separate; Optimizely maintains a migration guide for teams moving between them. That split matters when you evaluate the platform, because which product you need depends on who runs your tests — and because moving between the two is itself a migration, not a setting. A team whose marketers run Web Experimentation but whose engineers later want Feature-style tests signs up for a second product line and a migration project, not an upgrade.
On statistics, Optimizely's Stats Engine is well regarded and was built with Stanford researchers. It uses sequential testing by default, producing always-valid p-values with false-discovery-rate control, and it detects sample-ratio mismatches automatically. By design it is conservative: deliberately slow to declare a winner, and resistant to claiming results that later reverse. It is frequentist in approach — there is no Bayesian engine in the product.
On pricing, Optimizely does not publish prices. Pricing is typically quote-based, sold through enterprise contracts, commonly with annual or multi-year commitments, and there is no permanent free tier (a free trial exists). The practical effect: to learn what Optimizely costs, you have a sales conversation first.
ProveBetter is a different shape of product. These are the decisions behind it.
Published, event-volume pricing with a free tier. ProveBetter's prices are on the pricing page: Free at $0 with 1M events per month and no credit card, Small at $199/mo (5M events), Medium at $399/mo (25M), Enterprise at $1,999/mo (100M). Every analytic feature is on every tier — tiers scale on event volume, never on seats or gated features. You know the price before you sign up, and you can run a real test before you pay anything.
One platform, no Web/Feature split. Client-side tests (one snippet) and server-side tests (plain HTTP) run in the same account, read out in the same dashboard, and use the same statistics. On Optimizely, testing in code means Feature Experimentation — a separate product line from Web. On ProveBetter there is no second product to buy when you want to test in the backend.
Both stat engines, in plain language. Every result runs a frequentist and a Bayesian engine side by side, each summarized in a plain-language verdict — no statistics degree required. Optimizely is sequential-frequentist only; VWO popularized the Bayesian "chance to beat"; ProveBetter shows you both. Trust banners flag when the numbers shouldn't be trusted — an SRM watch and a small-sample validity notice — and if you rebalance traffic while a test is running, the dashboard says "traffic changed mid-test — results may be biased" instead of pretending nothing happened.
Server-side testing without a second product. Server-side tests are two plain-HTTP calls — POST /api/assign to assign a variant and POST /api/events to report outcomes — with sticky assignment via a stable visitor id. No SDK required; any backend that speaks HTTP can run a test. The API reference is the technical source of truth, and the server-side testing guide covers when testing in code is even the right call.
A flat, honest feature set. 2–5 variants per test (A/B/C/D/E); live traffic-percentage adjustment mid-test with sticky assignment; future scheduling; one-click winner rollout to 100%; one target metric per test (call, click, form fill, sale, signup, retention, or a custom event); a full audit trail of every change; CSV/JSON and API export on every tier.
And the honest inverse: ProveBetter has no visual editor. Variant content is authored in the builder — heading and body copy per variant — not by clicking on a rendered page. If your workflow depends on a visual editor, that is a real gap, and Optimizely's Web Experimentation is the stronger fit. We are not claiming to replace every Optimizely workflow; we compete on price transparency, self-serve, and simplicity. The client-side install is one snippet when you want it.
| ProveBetter | Optimizely | |
|---|---|---|
| Pricing model | Published event-volume tiers, $0–$1,999/mo; every feature on every tier; no credit card for Free | Typically quote-based, enterprise contracts; no published prices; no permanent free tier |
| Where decisions run | One platform: client-side (one snippet) and server-side (plain HTTP, /api/assign + /api/events) | Split across two products: Web Experimentation (browser, visual editor) and Feature Experimentation (code, SDKs/APIs) |
| Stats engines | Frequentist and Bayesian on every result, with plain-language verdicts and trust banners | Sequential Stats Engine (built with Stanford): always-valid p-values, FDR control; frequentist only, conservative by design |
| Setup time | Sign up free with no card; client-side is one snippet, server-side is two API calls | Sales-led quote and contract first, then choose between Web and Feature; free trial, no free tier |
The honest comparison on price: Optimizely does not publish pricing, so we cannot line up like-for-like dollar figures — and we won't invent any. What is documented is that Optimizely pricing is typically quote-based, sold through enterprise contracts, with no permanent free tier.
ProveBetter, by contrast, publishes everything:
| Plan | Price | Events per month |
|---|---|---|
| Free | $0 | 1M |
| Small | $199/mo | 5M |
| Medium | $399/mo | 25M |
| Enterprise | $1,999/mo | 100M |
Two implications are worth spelling out. First, the published price is the whole price: no per-seat add-ons, no gated features — a feature on the Free tier is the same feature on Enterprise. Second, you can evaluate ProveBetter with a real test before paying anything, which makes for a comparison you can run against any Optimizely quote you receive: run the same experiment in both, and decide with data instead of a sales conversation.
Optimizely has capabilities ProveBetter does not, and for teams that need them it is the right tool:
POST /api/assign and POST /api/events with a stable visitor id — the API reference walks through the flow. For client-side tests, swap the snippet and re-create variant copy in the builder (install). Historical results don't transfer — you start a fresh experiment with a clean read.If you want published pricing with a real free tier, both stat engines in plain language, and client-side plus server-side testing without a platform split, start on the pricing page and check whether your event volume fits. If you need a visual editor, MVT, or personalization, Optimizely remains a legitimate choice — and now you know exactly what the difference is before you talk to either vendor. There is no sales sequence and no procurement cycle on our side: the Free tier is the same product as the paid tiers, just with a smaller event budget, so the fastest way to test these claims is to run one. See the product on the homepage, read the server-side testing guide, and judge us against the list above.