A/B test any website
Built for speed and simplicity. A streamlined alternative to complex testing tools.
Works where you work
Launch in <45 seconds
Fastest in the market, built for speed and simplicity
At just 5.4KB and served on a CDN, Stellar's pure JS script is 25x smaller than competitors like VWO or AB Tasty. With minimal dependencies and a fixed size regardless of test count, it preserves your website's speed, Core Web Vitals, user experience, and SEO performance.
Why we stand out
Create variants with our visual editor
✓ No-code visual editor
Install our snippet to access a WYSIWYG editor directly on your site. Works with any website.
✓ Dynamic Keyword Insertion
Personalize your landing pages copy with dynamic keyword insertion. Message match your ads. Zero coding required.
✓ Custom JS and CSS
Add custom JavaScript and CSS for more granular control over your page. Perfect for advanced tweaks and precise adjustments.
✓ Easy Goal Setup
Set your conversions in seconds with a simple interface. Choose one based on page visits or specific user actions. No coding needed.
✓ Track multiple conversions
On a per experiment basis, you can track different conversion events to get a more comprehensive view of your results and understand down funnel performance.
Track conversions, effortlessly
Real time analytics,
Integrates with GA4
✓ Real time data
See your data in real time with a straight forward interface. Understand exactly what's happening with each variant.
✓ Integrates with GA4
Easily integrate your Stellar data with GA4 or other tools such as Segment or Mixpanel.
✓ Dynamic Message Matching
Personalize your landing pages to match your ad copy using dynamic keyword insertion. Show location-specific content with built-in geo variables. Create relevant experiences that talk to your user.
✓ Campaign Performance Insights
Analyze performance by UTM parameters to understand which campaigns and ad groups convert best. Segment your data by source, medium, campaign and more to make data-driven optimization decisions.
Message-match your landing page for every ad
Split test your way to market fit and beyond
A solid product, but don't take our word for it
Jake M. — Performance Marketer
Other testing tools have a million features I don't need. Stellar focuses on what actually matters: speed, ease of use, and great analytics.
Richard R. — E-commerce Owner
Stellar is the real deal. No unnecessary features, no steep learning curve. Just quick tests that actually improve our store.
Ben C. — Growth Hacker
It does the job without slowing down our pages. If you're running tests and care about performance, this is the tool to use.
Mike T. — Founder @ DTC Brand
Stellar is refreshingly lightweight and ridiculously easy to use. My team got experiments running without having to call in developers. Game changer!
Lauren K. — Growth Marketer
Setting up my first test took no more than 5 minutes. Easily the best testing tool I've used.
Jason B. — CRO Specialist
We were looking for a Google Optimize alternative. Stellar is so simple yet incredibly powerful. And their usage based pricing makes us save a TON compared to our previous contract with VWO.
Sarah J. — Marketing Lead
Stellar keeps it simple but does everything you need. Fast, lightweight, and no unnecessary complexity. Also, their support team are absolute legends.
David R. — SaaS Product Manager
Switched to Stellar after dealing with slow, clunky testing platforms. The difference is night and day. Setup is fast, the script is tiny, and our site loads just as fast as before. Highly recommend.
Tom G. — Lead Designer
Ran my first test in five minutes and without a developer. Reporting is clear, setup is easy, and it just works.
Emily W. — Conversion Specialist
The perfect alternative to all those bloated testing tools. Their support team actually knows A/B testing and helps when you need it.
Pricing
Free
Up to 25k MTU
Built-in analytics
Visual web editor
Custom CSS & JS editor
AI editor assistant
Basic A/B testing
Limited variants & goals
Limited concurrent experiments
Pro
50k MTU included
Unlimited variants
Unlimited concurrent experiments
Advanced targeting rules
Dynamic keyword insertion
Priority support
Enterprise
Custom MTU volume
Custom solutions
Integrations support
Unlike competitors who charge in fixed large blocks, we dynamically bill in small increments of 1k MTU, ensuring you never overpay
Compared to average competitors like VWO's $4,700/year for 50k MTU, our equivalent annual cost is just $1,118
We only count users who actually see experiments. Multiple experiment views from the same user count as just 1 MTU