A/B testing & CRO consultant
A/B testing & conversion rate optimization services
Understand where your product loses conversions, find what to improve and evaluate changes through controlled experiments. I combine user research, behavioral data and A/B testing so product teams can decide with evidence, not guesswork, what to roll out.
Experience
75+ A/B tests
Analytics & testing
GA4, Kameleoon, AB Tasty, Hotjar
What is conversion rate optimization?
Improve product performance through evidence-based experimentation
Conversion rate optimization (CRO) means finding where your funnel loses people and improving it step by step. A/B testing is its measuring instrument: it shows whether a change works on a defined metric, not why. I report results with their uncertainty and combine them with research when the why matters.
The effect on your metric
Whether a change improved, hurt or didn’t change the outcome you measure.
Whether the difference is likely real
Statistical analysis separates signals from random variation.
What to roll out
A clear decision basis for the next step.
When is A/B testing right for your product?
A good fit if
You have enough traffic and a clear conversion goal, but conversion is below expectations.
A/B tests run without clear, research-based hypotheses.
A change needs evidence before a full rollout.
Test results are hard to interpret or the team disagrees about them.
Tracking works, so changes can be measured on a clear primary metric.
Not the right fit if
Your traffic is too low for reliable tests. Start with qualitative research.
You first need someone to set up analytics or tracking.
The decision is already made and the test should only confirm it.
You want to know why users struggle. That’s usability testing or user research.
Not sure what to test first? A UX audit shows where your funnel loses people and which changes are worth testing.
Website A/B testing
What can we optimize and test?
Checkout, landing pages, product pages and key user flows, tested with real traffic in your product.
Checkout and conversion funnels
Checkout A/B testing for checkout steps, form fields, payment options and calls to action, to see their impact on completion rates.
Landing and product pages
Landing page A/B testing for messaging, page structure, information hierarchy and product presentation.
Pricing and payment communication
How prices, discounts and payment options are shown. These changes can lift conversion or quietly hurt it.
User flows and feature changes
How changes to navigation, interactions or product features influence key user behaviors.
How the experimentation process works
STEP 1
Analyze the funnel
We look at your data and goals to find where conversion is lost and which questions matter most.
STEP 2
Build hypotheses
I turn behavioral evidence and research into testable hypotheses and prioritize them by impact and effort.
STEP 3
Design and set up the test
I define variants, primary and guardrail metrics, sample size and duration, so the result is reliable before the test goes live.
STEP 4
Run and monitor
The test runs in your testing tool. I support setup and quality assurance with your team and check data quality while it runs.
STEP 5
Analyze and decide
I analyze the results and we decide together: roll out, iterate or stop and what to test next.
What you’ll receive
Every test is documented in an A/B testing report from hypothesis to decision. It feeds into your experimentation roadmap, so your team knows what was tested, what happened and what to test next.
A hypothesis backlog
Research-based test ideas, prioritized by expected impact and effort.
A test plan
Variants, metrics, sample size and duration, agreed before launch.
Setup support
Help with configuring the test in your tool, together with your team.
Statistical analysis
A clear read of the results, including uncertainty.
A rollout recommendation
Roll out, iterate or stop, with the reasons behind it.
Ready to test changes with confidence?
A/B testing case studies and results
Two real experiments: a payment communication test showed +26% purchase conversion and became the basis for a rollout decision. A crossed-out price test showed −16.6% conversion and stopped a risky pricing logic before it became standard. Each case study shows the hypothesis, the experiment design, the result and the product decision.
A/B testing cost, timeline and requirements
Not sure yet what to test? The fixed-price UX audits below are a first step that shows which changes are worth testing.
What drives the cost
The number of experiments, how much research is needed first and whether I support your team once or on an ongoing basis.
What you need
Enough traffic on the tested page, working tracking on a clear primary metric and a testing tool such as Kameleoon.
How long a test runs
Until the planned sample size is reached and full business cycles are covered. That usually takes several weeks, depending on traffic.
Prices are net; VAT is added based on your country and tax status.
Independent CRO consultant
Why work with me?
I’m a UX researcher and psychologist (M.Sc.) working as an independent A/B testing and CRO consultant. You work with me directly, from the first hypothesis to the rollout decision.
Research meets experimentation
I combine user research with A/B testing, so hypotheses are grounded in evidence and results are explained, not just reported.
75+ A/B tests
Hands-on experience with pricing and payment communication experiments, using GA4, Kameleoon, AB Tasty and Hotjar.
Statistics you can rely on
Experienced analysis supported by AI, with sample sizes planned upfront and results reported with their uncertainty.
FAQ
Frequently asked questions
Let’s discuss your next experiment
Tell me about your funnel and the decision you’re facing. In a free 30-minute call we clarify whether a test makes sense, what to measure and what it takes to get a reliable result.
Diana Szczepanik
UX Researcher & CRO Consultant, Psychologist (M.Sc.)