Otter vs Google Optimize
The free Google experimentation product retired in 2023. Google Optimize is gone — the practical question is which supported tool replaces it. Here's how Otter maps to what Optimize did.
About Google Optimize
Google Optimize was a free visual A/B testing and personalization tool connected to Google Analytics. Google retired both Optimize and Optimize 360 on September 30, 2023 — any experiments still active on that date simply ended, deployed personalizations reverted, and no data migration path was provided. Google has confirmed that A/B testing is not returning inside GA4.
Which should you pick?
Choose Otter if…
- You want the Optimize workflow back: visual editor, A/B and redirect tests, personalizations
- You want your GA4 conversion events to keep working as experiment goals
- You want self-serve setup at a published price, not an enterprise contract
Choose Google Optimize if…
- Nobody should choose Google Optimize — it no longer exists. The comparison below shows what Otter restores and adds.
Feature comparison
| Feature | Otter | Google Optimize |
|---|---|---|
| Availability | Available now | Discontinued September 30, 2023 |
| Price | From $39/mo flat, unlimited visitors | Was free (Optimize 360 was paid) |
| Visual editor | Ended with the product | |
| A/B and A/B/n testing | Unlimited concurrent tests | Had a concurrent-test cap on the free tier |
| Split URL / redirect testing | Ended with the product | |
| Multivariate (factorial) testing | A/B/n instead (no factorial) | Had MVT (16-variation cap) |
| Personalization | Targeted personalization test type | Ended with the product |
| GA4 events as goals | Native GA integration (retired) | |
| Revenue tracking | Built-in, with multi-currency conversion | |
| Frequentist and Bayesian analysis | Per-test choice | Bayesian only |
| Auto-stop rules | ||
| REST API + MCP for AI agents | All plans | |
| Active support and updates |
Information based on publicly available data as of July 2026, including Google's official sunset documentation. Features may change — verify details against current sources.
What actually happened to Google Optimize
Google announced the sunset in January 2023 and shut Optimize down on September 30, 2023. It wasn't a soft landing: experiments still running on that date ended, personalizations deployed through Optimize reverted, historical results had to be downloaded before the deadline, and there was no export or migration tooling. Google pointed users to third-party A/B testing providers — naming AB Tasty, Optimizely, and VWO as GA4 integration partners — and confirmed that native experimentation is not coming back to GA4.
That left a lot of teams — by third-party estimates, millions of sites used Optimize — choosing between enterprise-priced replacements and going without testing.
Mapping Optimize's features to Otter
Otter covers the workflow Optimize users actually had: a visual editor for building variants on the live page, A/B and A/B/n tests, redirect (split URL) tests, and personalizations — Otter has a dedicated content personalization test type that serves targeted content to visitor segments, which was one of Optimize's most-used capabilities.
Two honest differences. Optimize offered factorial multivariate testing (capped at 16 variations); Otter runs A/B/n tests with any number of variants but doesn't do factorial combinations. And Optimize was free — Otter starts at $39/mo. What you get over free-Optimize is unlimited concurrent tests (Optimize capped them), revenue tracking with multi-currency support, auto-stop rules, a REST API and MCP server, and a product that's actively maintained.
The GA4 connection, restored properly
The thing teams miss most about Optimize was that goals lived in Google Analytics. Otter restores that: existing GA4 conversion events can be used directly as experiment goals, so the conversions you already trust keep being the ones you test against. Otter can also forward experiment impressions and conversions into GA4 for analysis there.
Google's endorsed replacements integrate with GA4 by pushing data into it or importing audiences — using your GA4 events as experiment goals is rarer, and it was the heart of the Optimize workflow.
Migrating from Optimize (or from nothing)
If you've been without testing since the sunset, migration is a fresh start: install Otter's snippet (one script tag with a one-line anti-flicker style the SDK removes automatically), rebuild your experiments in the visual editor or wizard, connect GA4 if you want GA4-event goals, and launch. Historical Optimize results can't be imported anywhere — Google retired the data along with the product.
Statistically, you're trading Optimize's Bayesian-only reporting for a per-test choice: Bayesian chance-to-beat, or frequentist analysis at 80/90/95/99% confidence with thresholds automatically adjusted for multi-variant tests.
The bottom line
Google Optimize is no longer available, so the practical decision is which supported tool replaces its visual experiments and Analytics-connected goals.
Otter covers the core migration path — visual editor, A/B/n and redirect tests, personalizations, GA4 event goals, revenue attribution, and statistically sound reporting — and adds what free Optimize never had: unlimited concurrent tests, auto-stop rules, and API/MCP automation.
Unlike the enterprise replacements Google pointed to, Otter is self-serve with flat per-project pricing and unlimited visitors.
Otter vs Google Optimize — common questions
What replaced Google Optimize?
Google ended Optimize on September 30, 2023 and pointed users to third-party tools, naming AB Tasty, Optimizely, and VWO as GA4 integration partners. Those are enterprise-priced platforms; Otter is a self-serve replacement for teams that need visual A/B tests, split URL tests, personalizations, revenue tracking, and GA4-connected goals.
Can I migrate Google Optimize experiments to Otter?
You can rebuild them, but not import them — Google provided no export or migration path when it retired Optimize, and historical results are gone unless you downloaded them before the sunset. In Otter: install the snippet, recreate each experiment and goal, verify the variants, then launch.
Does Otter integrate with Google Analytics 4?
Yes, in the direction that matters most for Optimize refugees: existing GA4 conversion events can be used directly as experiment goals. Otter can also forward experiment data into GA4 for analysis there.
Does Otter have multivariate testing like Optimize did?
Not factorial MVT. Optimize supported multivariate tests with up to 16 variations; Otter runs A/B/n tests — one factor, any number of variants — with confidence thresholds automatically adjusted for the number of challengers. Most teams that used Optimize's MVT sparingly find A/B/n covers their real usage.
Will Google bring back Optimize or add testing to GA4?
Google has said no — GA4 has no built-in A/B testing and Google confirmed Optimize's functionality is not being rebuilt inside GA4. GA4's role is analysis of experiments run by third-party tools.