A/B Testing Agency
An A/B testing agency plans, builds and runs A/B tests on your website for you. We design, build, QA and launch tests, read the results, and keep only the changes that win.
Last updated October 26, 2026
What does an A/B testing agency do?
An A/B testing agency decides what to test on your site, then builds, runs and analyzes the tests.
An A/B testing agency that only builds and runs tests is doing the easy half. The hard half is the conversion research that decides which tests to run, and that is where most of the lift comes from. ConversionTeam is both: we run the full CRO process - analytics, heatmaps, user testing, and prioritization - and then design, build, QA, and analyze the tests. You get the research and the execution from one team.
Who it's for
When should you hire an A/B testing agency?
Companies hire one when they want to start a testing program, revamp one that isn't producing results, expand one that works, or outperform the competition.
Start an A/B Testing Program
They need a best in class A/B testing solution to stay competitive in their niche or market.
Revamp an existing program
Their current testing program is not producing results or is bogged down due to resource constraints.
Expand an existing program
They have a successful A/B testing program but want to add turnkey resources to increase velocity.
Outperform the competition
CRO is a competitive advantage that is required in competitive markets.
Not sure you have the traffic? See how much traffic you need for A/B testing.
What's included when you hire an A/B testing agency?
Expect the research, the design, build and QA of every test, a testing tool, and a report on each result.
- The audit is an analytics review, user testing against a competitor, a poll, heatmaps and session recordings; you get a prioritized list of fixes.
- You review a mockup first; developers build and QA checks; then a preview link before it goes live.
- QA across browsers with LambdaTest; results read by browser.
- You get a progress report on every test: what ran, the result, and what we test next.
- We'll use Nantu if you don't have a testing tool, and we're experienced with whatever testing tool you're already using.
- A winner can be served to all traffic through the testing tool until it's built in.
- The team includes analysts, copywriters, designers, developers and QA.
We're testing-tool agnostic. We have experience with the major platforms, Optimizely, VWO, AB Tasty, Adobe Target, Convert, Kameleoon, Dynamic Yield, Monetate and SiteSpect; product experimentation tools such as Statsig, LaunchDarkly, Eppo, GrowthBook and PostHog; Shopify testing apps such as Intelligems, Shoplift and Shopify Rollouts; and smaller tools such as Omniconvert, Webtrends Optimize, Zoho PageSense, ABlyft and Varify.io.
How does a good A/B testing agency pick and run tests?
Tests come from your own analytics and user research, not a generic list.
- We prioritize the pages with the most traffic and drop-off first.
- The audit splits findings into changes to just make and a shorter list to test.
- Each test changes a few elements, not a whole page.
- Every test runs at least two full weeks.
- We recommend the order; you can swap a test; the backlog keeps growing.
- An A/B testing agency should publish a win rate and show you losing tests, not only winners.
What does an A/B testing engagement look like?
Tests start in week 2; the audit research runs alongside them; later tests come from the audit's prioritized list.
- Intake form, then a kickoff call to go over it and pick the first test.
- Meetings cover the running tests, results so far, what's next, and your feedback.
- Every program is month to month; you own the test code and data.
A/B testing agency, CRO consultant or in-house team?
It comes down to whether you can staff a full testing team and keep it busy.
In-house testing works once you have the full stack of people - a strategist, a designer, a front-end developer, a QA resource, and an analyst - plus a testing platform. That is a lot of headcount to keep busy. An agency gives you that whole team on a monthly program, usually for less than one senior hire, plus pattern recognition from thousands of tests across other sites. Iterate includes all of those roles and the testing tool, so you can run a serious program without building the department.
Published rates on the consultant pages we reviewed run $75 to $300 an hour, $5,000 to $20,000 a month on retainer, and $8,000 to $25,000 for a project. More on hiring a CRO consultant.
Teams without the bandwidth to run a testing program plug us in.
How much traffic do you need for A/B testing?
About 60 meaningful conversion actions a month. At that level we also track engagement and micro conversions to augment the primary KPI. Below that we will tell you straight, and focus first on higher-traffic pages, bigger swings, or research-led changes, so you are not waiting months for an inconclusive result.
How much does an A/B testing agency cost?
Monthly programs start at $2,500 (AMPLIFY Startup) and Iterate programs at $3,500. The Hitlist CRO Audit is a one-time project at $3,500 to $10,000. Every program is month to month, and Nantu, our testing platform, is included, so there is no separate tool fee.
Specialist CRO agencies publish monthly retainers from $2,000 to $5,000 at the entry level, $5,000 to $10,000 in the middle, $10,000 to $20,000 at the top, and $20,000 to $35,000 and up for enterprise programs. A decent testing tool runs $550 to $3,500 a month, billed to you.
How to choose
How do you choose an A/B testing agency?
Check where their tests come from, who builds them, whether they publish a win rate, how results are measured, which tool they use and how fast they test.
Plenty of agencies can build and run a test. The research that decides which tests to run is where the lift actually comes from - so the bar is higher than "can they code a variation." Here is what separates a program that compounds from one that stalls, and how Iterate measures up. For the full breakdown, read our guide: what a CRO agency does and how to choose the right one.
- Research before tests, not just execution
- The tests that win start with conversion research - analytics, heatmaps, and user testing. We run the full CRO process first, then build the tests, so the roadmap is earned, not guessed.
- A full in-house team, not just developers
- Strategy, design, front-end development, QA, and analysis under one roof. You are not hiring a dev shop and sourcing the strategy somewhere else.
- A win rate they will actually publish
- Ours is 61.1% across decisive tests, from a program that has run 8,000+ A/B tests.
- Results proven in your own analytics
- Every lift is measured in your analytics platform, not self-reported. Be wary of any agency that prices on percent lift - that number is easy to inflate and hard to verify.
- Their own testing tool, or yours
- Iterate includes Nantu, our testing platform, at no extra cost and with no volume limits - or we work with the tool you already license.
- Velocity matched to your traffic
- The right program runs as many tests as your traffic can support - 2 to 5 cycles at a time - so you learn fast without chasing inconclusive results.
What results has ConversionTeam delivered?
Each card links to the full case study.
+90.2%Conversion rate liftCase study · AB TestingCustomer Review Positioning: 90% Conversion Boost
A/B test for a premium industrial coatings retailer revealed a surprising insight: displaying 5-star customer reviews outperformed technical durability messaging by a staggering 90.2%. Even for highly technical products like marine and pool paint, social proof proved more persuasive than performance specifications. This case study demonstrates how proper review positioning can dramatically impact conversion rates and revenue, challenging conventional wisdom about marketing technical products. Find out how we implemented this strategy and the specific results we achieved.
Read case study
+8.2%Conversion rate liftCase study · AB TestingFree Shipping Test Drives 8.2% Conversion Boost
How Strategic Shipping Promotions Boosted Our E-commerce Conversion Rates A data-driven case study on effective multi-touchpoint shipping messaging Free shipping continues to be one of the most powerful incentives in e-commerce, but how you communicate these offers can dramatically impact their effectiveness. Our recent optimization project revealed surprising insights about how new visitors respond to shipping promotions across their shopping journey. Key Insights Our data revealed new visitors responded exceptionally well to shipping promotions. The multi-touchpoint approach created consistent engagement opportunities throughout the customer journey. Analysis showed three key success factors: New visitors engaged strongly with shipping messaging Consistent promotion across touchpoints boosted both conversion rates and average order values The message resonated across all devices [Continue reading to discover our recommended implementation strategy and see the impressive results...]
Read case study
+29.7%Conversion rate liftCase study · AB TestingForm Testing Increases Patient Signups 30%
A premium women's health center sought to improve patient acquisition through their website. Through strategic form optimization and A/B testing, we transformed their underperforming contact form (2.17% conversion rate) into a 29.7% more effective patient acquisition tool.
Read case study
I couldn't be more impressed. Their team ran an in-depth audit that identified high-value opportunities, then a game plan of A/B tests to validate them - and nearly every test they recommended outperformed the control. Rigorous and data-driven, no guesswork.
We've worked with ConversionTeam since 2018 and are very happy. Their collaborative spirit and out-of-the-box ideas have significantly amplified our CRO efforts and added new dimensions to our strategy.
An outstanding experience. When we went looking for help optimizing conversions, two people I hold in the highest regard - who don't even know each other - both recommended Devon. We've been blown away by their expertise, professionalism, and results.
Responsive, timely, and the results and expertise speak for themselves. We bring them in across multiple client engagements.
Devon is a real CRO rockstar. He looks at a site and immediately hones in on the opportunities for improvement, and backs up every recommendation with testing. Highly recommend.
Mike BelascoFounder & AdvisorThey provide elaborate reporting on every test, with clear KPIs where we can identify winners to implement - conversion-rate increases, more ecommerce purchases, and higher engagement. Communication is easy and their project management is excellent.
Devon was a great partner when we needed to improve our website's user experience. His team gave us a thorough audit of our top pages and a free heatmapping tool we still use today. Highly recommend, especially if you're in lead gen.
Working through tests with ConversionTeam has been great. Their project management is top-notch, and their knowledge base is what stands out - we have no plans to change the relationship any time soon.
ConversionTeam was excellent to work with and delivered exactly what we were looking for. They ran a CRO audit of our site; their insight was incredibly valuable and helped us advance toward our goals with confidence. Professional, organized, and thorough.
ConversionTeam has had a significant impact on our conversion rate - a good uplift, and especially an increase in revenue. We're impressed with their personalized approach and deep understanding of our needs.
We're seeing 210x ROI and a 22% lift in conversion rate - it's hard to measure all of their impact. We sold out of almost all our stock; we weren't ready for the lift they'd provide. They run a tight ship and always come to meetings prepared.
Is there a guarantee?
ITERATE and ITERATE Enterprise carry the 30% lift in 90 days guarantee: if winning tests have not delivered a 30% conversion rate improvement in your first 90 days of active testing, we keep working free for up to 3 more months. ITERATE Lite carries a 20% guarantee on the same terms.
AMPLIFY Startup carries no guarantee. More on the Iterate program.
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