How to Migrate from Google Optimize to Stellar

Google Optimize was discontinued on September 30, 2023. If you still have the old snippet on your site or experiments you never recreated, this checklist walks you through migrating to Stellar — a free Google Optimize replacement with a visual editor, multiple goals, and GA4 integration.

Migration checklist at a glance

Step	Action	Time estimate
1	Audit active Optimize experiments and export screenshots/notes	15–30 min
2	Create a free Stellar account	2 min
3	Remove the Google Optimize container snippet	5 min
4	Install the Stellar snippet (one line of code)	5 min
5	Recreate experiments in the visual editor	30–60 min per test
6	Set up conversion goals and GA4 event forwarding	15 min
7	Launch and verify variants render correctly	10 min

Step 1: Document what you had in Google Optimize

Before touching code, inventory every experiment that was live or paused in Optimize:

Experiment name and type (A/B, redirect, personalization)
Page URLs and audience targeting rules
Primary and secondary goals (clicks, pageviews, custom events)
Variant screenshots or HTML notes for each variation

If you are unsure whether GA4 Experiments alone covers your needs, read Google Optimize vs GA4 Experiments first.

Step 2: Create your Stellar account

Sign up for Stellar's free forever plan — up to 25,000 monthly tracked users, no credit card required. This replaces Optimize's former free tier with full access to the visual editor and multiple conversion goals.

Step 3: Remove the Google Optimize snippet

Find and delete the Optimize container script from your site. Common locations:

Google Tag Manager — remove the Optimize tag or container
Theme header (WordPress, Webflow custom code) — search for optimize.js or GTM- Optimize containers
Direct <script> tag in your HTML <head>

Leaving the old snippet can cause console errors and slow page loads. For platform-specific removal tips, see Google Optimize alternative for WordPress or Google Optimize alternative for Webflow.

Step 4: Install Stellar

Add the Stellar snippet to your site — one async script tag in the <head>. The script is 5.4KB, so it is significantly lighter than most Optimize replacements.

If you saw flicker when running Optimize tests, enable Stellar's anti-flicker snippet during setup.

Step 5: Recreate your experiments

Use Stellar's visual editor to rebuild each variation:

Open the page you want to test
Create a new A/B experiment in Stellar
Use the WYSIWYG editor to change headlines, CTAs, images, or layout
For advanced changes, add custom JavaScript or CSS (same workflow many Optimize power users relied on)

Feature mapping from Optimize:

Google Optimize	Stellar
Visual editor	WYSIWYG editor + custom JS/CSS
Audience targeting	URL rules, device, country targeting
Objectives / goals	Multiple conversion goals per experiment
GA4 link	gtag / GTM event forwarding

Step 6: Set up goals and GA4 continuity

Stellar tracks conversions natively, but you can also forward experiment data to GA4:

Add a click goal for button or link conversions
Add a pageview goal for thank-you or confirmation pages
Use custom JavaScript in Global Variant JS to fire gtag events with experiment and variant IDs

This keeps your GA4 reporting consistent with how Optimize sent data to Universal Analytics / GA4.

Step 7: Launch and verify

Before going live:

Preview each variant on desktop and mobile
Confirm targeting rules match your old Optimize audiences
Check that the anti-flicker snippet (if used) hides flash correctly
Verify GA4 events in DebugView if you set up forwarding

How long does migration take?

Most teams migrate a single active experiment in under an hour. A full site with 3–5 experiments typically takes half a day, mostly spent recreating variants in the visual editor.

Ready to migrate?

➡️ Start for free with Stellar — no credit card required
➡️ See the full Google Optimize alternative page for feature comparison
➡️ Book a demo if you want help planning your migration

Try Stellar A/B Testing for Free!