A/B testing that respects your traffic and your budget
Most A/B testing tools charge you more as your site grows. We built Otter A/B because we think that's backwards. You should pay for what you use, not be taxed on your success.
Why we built this
The problem with A/B testing pricing
We've run A/B tests for years across e-commerce, SaaS, and content sites. The tools were always the same: powerful enough, but with pricing designed to scale against you.
Hit 100K visitors? Time to upgrade. Cross 500K? Another tier. Run a successful campaign that drives traffic? Congratulations — here's a bigger invoice. The industry calls this “MTU-based pricing” (Monthly Tested Users), and it means the better your site performs, the more you pay for the exact same tests.
We built Otter A/B on a different principle: charge for projects, not visitors. Every plan includes unlimited tests, unlimited visitors, and the full feature set. The only difference between plans is how many projects you can run.
The result is a testing platform where you can focus on learning what works, without watching a usage meter or worrying about overage charges at the end of the month.
Our Mission
“Too many product decisions are made on intuition. We built the A/B testing platform we wanted to use: fast to set up, statistically rigorous, and clear about when results are decision-ready.”
The Otter A/B Team
Our Values
What we stand for
Accuracy
Statistical rigor is non-negotiable. We use established frequentist methods, adjusted decision thresholds, and transparent sample-size estimates. No vanity metrics, no hardcoded confidence shortcuts.
Simplicity
One line of code to install. Five minutes to your first test. Complexity is the enemy of experimentation — we keep the interface focused and the setup fast.
Performance
Our SDK is under 9KB with built-in anti-flicker and async loading. Your visitors should never know they're being tested.
Fair pricing
We charge per project, not per visitor. Your bill doesn't go up just because your traffic does. No MTU caps, no overage charges, no surprises.
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