Conversion Rate Optimization

Same traffic,
more conversions.

You have the traffic. You have conversions. But you also have revenue slipping through the cracks. We find it, test for it, and ship only what the data proves.

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01 / FOR YOU IF

CRO works in the right conditions

It’s not the right tool for every business at every stage.
Here’s an honest picture of who gets the most out of it.

You have analytics implemented

You can’t improve what you haven’t measured. Measure first, improve afterwards.

You have steady traffic

A/B testing needs volume to reach statistical significance. Roughly 5,000+ monthly sessions on target pages is a workable starting point.

Conversions are flat or falling

Traffic is there but people aren’t completing purchases, signing up, or enquiring. You know something is wrong but not exactly what.

You want ongoing improvement

CRO compounds over time. Each experiment informs the next. A one-off audit helps, but a sustained engagement gets real results.

You’re open to being wrong

Good CRO challenges assumptions. The best clients are curious, not defensive, when data contradicts what they believed about their users.

Not the right fit if…

Your site has very little traffic, or you’re looking for a one-time quick fix. If you’re at an earlier stage, a UX audit or a well-structured website build might be a better starting point.

02 / WHAT WE DELIVER

Proof, not guesswork.

Everything a proper testing program needs. Nothing that just looks busy.

Research that finds the leak.

Analytics deep-dives, heatmaps, session recordings, and user research. We find where conversions are leaking, and why.

A roadmap, not a wishlist.

Every opportunity ranked by impact, confidence, and effort. We test what moves the needle first, not what’s easiest to build.

Experiments, start to finish.

We write the hypotheses, design the variations, and build the tests. You approve, we run.

Analysis you can trust.

Proper statistical significance, Bayesian where it fits. No cherry-picked wins, no calling a test early because the line looks good.

Lessons logged, winners shipped.

We roll out what works and document what doesn’t. Every test sharpens the next one, even the losers.

03 / HOW WE WORK

Three rules. No exceptions.

Every experiment answers to the same three rules. They decide what we test, why, and whether it ships.

01. Start with evidence.

A hunch is just a guess. A hypothesis is a guess with data behind it, and a real chance of being right. We don’t test at random or chase whatever’s trendy. Every experiment starts from what your numbers and your users are already telling us.

02. Design for outcomes.

Pretty doesn’t pay. The only thing that counts is whether the number moves: more signups, more checkouts, more revenue. We don’t chase prettier pages or higher engagement, we chase the metric that actually matters to your business.

03. prove it, don’t guess.

A change isn’t a win until the test proves it. Not a promising trend, not a gut feeling. Real statistical confidence, or it doesn’t ship. And a test that disproves your idea has still done its job.

04 / PROOF

Small changes. Big numbers.

At PrintAbout, our experiments surfaced more than 10 million in discovered annual revenue. A few of the wins behind that number.

UX / PRODUCT DESIGN

CRO

We had a killer deal, our users didn’t see it…

Our housebrand cartridges were cheaper than the big-name stuff—better margins for us, better prices for customers. But people kept buying the expensive option anyway.

We led the UX strategy and design across two rounds of testing, using clickmaps, user interviews, and A/B experiments to figure out why.

Why it mattered

We knew our housebrand products delivered great value, but having a good deal isn’t enough. People choose what feels safe over what is smart, especially when they’re unsure.

This project showed how easily uncertainty can override logic when people are in doubt. Familiarity wins. Every time. But the right design can shift that behavior without changing anything about the offer.

We set out to boost housebrand conversions. What we actually did was help people make a more informed choice. Not by pushing it more, but by showing more value.

We helped users choose a product with the same quality, but for a better price per ml. At the same time, we boosted the margins for the company.

Sometimes the best outcome isn’t more buyers. It’s more confident ones.

The problem

There were actually two problems working against us.

First, users weren’t even seeing the switch. They’d land on the page, see the default OEM option, and buy it immediately. The housebrand alternative might as well have been invisible.

Second, even when users did notice the switch, it didn’t give them a reason to flip it. The interface showed the housebrand option, but it never highlighted what mattered: the cheaper price-per-ml.

So housebrand cartridges already felt like a risk, they weren’t the name you knew. And when the sticker price looked higher without an obvious reason why, people defaulted to the OEM option because it felt safer.

The better deal was there, in price-per-ml, but it was hidden in plain sight. And invisible value doesn’t change behavior.

We made value unmissable

First, we repositioned the product switch using the Gutenberg diagram, moved it where eyes actually land.

Switch interactions jumped +6.01%.

But conversions barely moved.
People saw the option. They just didn’t see the point in switching.

So we fixed the real issue: Clarity.
We spotlighted the ‘price-per-print’ and ‘price-per-ml’ inside the product switch, giving people hard proof they were getting more for less.

Impact

The moment users understood the deal, they took it.

On top of the +6.01% uplift in switch use we saw:
+45.16% uplift in housebrand transactions
+3.78% uplift in add-to-cart rate

We didn’t really convince ‘more’ users to buy products, but users made a more conscious choice which product they bought.

Our design didn’t just get attention, it earned trust.

This is how we turned hidden value into a 45% boost in housebrand transactions.

Side-by-side comparison of control and variant in a 2-column product detail page — redesigned by a data-driven UX designer to improve housebrand visibility.

ACCESSIBILITY

CRO

No one cares about accessibility… Until you prove it works

We knew the site had accessibility issues: missing focus states, poor contrast, barely any screen reader support.

With a 20+ year-old codebase, nothing is simple. But to be honest, code wasn’t the hardest part, mindset was.

So I did what I always do when something’s hard to sell: I turned accessibility into a business case.

I led the project from the start to the end. Analyzed user data, built buy-in across teams, and delivered WCAG-compliant improvements, without hurting conversions.

Why it mattered

PrintAbout’s audience skews older. Most of the users are over 50, and when we dug into the age data across the Netherlands, Belgium, Germany and France, it became obvious: This wasn’t an edge case, it affected a massive part of the user base.

These were real, paying customers. And we were making life harder for them.

If someone can’t see a button, read a text clearly, tab through with a keyboard, or tell which element is selected, you lose them. Simple as that.

But this wasn’t only about doing right by users. It was also a legal risk, and the clock was ticking.

The European Accessibility Act would be implemented from June 28, 2025. That wasn’t a nice-to-have milestone. That was hard deadline.

We had to move, but not just for compliance, but because inaccessible design also means lost revenue every day.

The problem

We weren’t starting from scratch.

The frontend has been evolving for over two decades,new code gets written properly, but chunks of the site haven’t been touched in years. Some of it’s so brittle that touching it risks breaking unrelated components.

But the deeper problem was organizational inertia. Accessibility had been a nice-to-have or was even seen as a burden.

Management worried about a return on investment and “taking accessibility too far.” One common quote: “blind users don’t use a printer”

Everyone assumed users were doing fine, but the ones who struggled often never made it far enough to complain.

From moral choice to metric

We needed proof to convince stakeholders of the monetary value of accessibility.

So we started small: a contrast test on the product detail page. We show a switch between original brand cartridges and our cheaper-per-ml housebrand option. The green text failed contrast checks, so we changed it to black.

That’s it. Just a color change. And we could test this ourselves without front-end developers, which made it dirt cheap.

Results:
Netherlands: +2.69% conversion (Bayesian: 69%)
Belgium: +9.74% conversion (Bayesian: 95%)

Yes, we tested button colors

That small win created momentum. If a contrast fix could lift conversions, what would happen if we tackled our primary CTA?

Our ‘Add to Cart’ button was failing contrast checks too.

We tested a darker version of our green, close enough to the original to keep brand consistency. Bolder options like pink, black, yellow, or red are still on the table, but this was the cleanest starting point.

Hypothesis:
Improving the CTA’s color contrast to meet WCAG guidelines will make the button more accessible and easier to perceive. As a result, the add-to-cart rate and conversion rate will remain stable or improve.

Impact

Netherlands: +0,43% uplift (Bayesian: 43%)
Belgium: +3,16% uplift (Bayesian 86%)
Germany: +7.16% uplift (Bayesian: 96%)
France: -7.90% (Bayesian: 3%) Likely tied to a younger user base.

Overall: Light average uplift across all markets.
Mobile: Strong performance across the board, backing our theory that contrast matters more on small screens with changing lighting.

We had enough proof. We rolled out the new accessible green as standard across the site as the experiment proved our hypothesis.

More users can now use our webshop just like people without a (permanent or temporary) impairment can.

Now what?

We’ve implemented visible focus states, improved text contrast across nearly the entire site, and made sure our primary CTA meets WCAG 2.1 AA contrast requirements. Link accessibility for screen readers is underway.

More importantly, the conversation inside the company has shifted.

Developers now see accessibility as an optimization, not a blocker. Management gets that compliance and conversion can go hand in hand.

And we’ve shown others that accessibility improvements can be measured and experimented with, just like anything else.

We didn’t just fix a button color.
We changed how the company sees accessibility: from a legal burden to a competitive advantage.

What happened next?

After the experiment, we wrote about it on LinkedIn.
It started a small riot.

Not everyone agreed that testing button colors was worth the time, accessibility or not. But the controversy created traction. The post went viral and became an example of how to safely implement WCAG-compliant changes without tanking your metrics.

That led to interviews, an invitation to speak at a Shopping Awards meeting for Expert Groups, and eventually a quote in one of Thuiswinkel.org Shopping Tomorrow’s bluepapers.

We didn’t just improve our site. We set a new standard for how to roll out accessibility changes. Safely, measurably, and without fear.

UX / PRODUCT DESIGN

CRO

PSYCHOLOGY

Shipping costs suck, but what if they didn’t?

Users were ready to buy, the add-to-cart ratio showed this. But they dropped off when they hit the shipping cost. We couldn’t remove the €4.95 fee, the margins were too tight for that.

So the question became:
If we can’t change the price, can we change how it feels?

For this project we led the strategy, research, design, and testing. The goal was to reframe the perception of shipping without touching the cost.

Why it mattered

We couldn’t remove the shipping fee, but it was costing customers. People would get all the way to the cart, see that €4.95, and decide not to go through with it.

It wasn’t really about the amount, prices were still lower than the competition. But it was the way it showed up like an unexpected extra.

What we learned from this project is that not all problems show up in the data. You only notice them when you start asking why people leave and don’t come back.

The problem

Shipping costs were mentioned in 31% of post-purchase surveys and customer service complaints. They made users feel like they were paying extra for nothing, a last-minute fine.

But the users who complained were the ones who completed the purchase. The bigger issue were the users who left without saying a word.

We dug into session recordings, complaint data, drop-off analytics and compared those to the post-purchase survey to piece together the moment of friction.

It wasn’t dramatic, just a small line in the order summary that quietly leaked conversions.

Designing for Perception, Not Price

We couldn’t remove the shipping fee, but we could reframe it. Over several iterations, we repositioned value around the shipping costs.

– Moved discount information directly above the shipping line to rebalance perceived value.
– Rewrote “Shipping Costs” to a more neutral “Shipping”
– Added trust cues like “With Track & Trace”
– Introduced outcome-based copy: “Carefully packed and quickly shipped”
– Used color, spacing, and labels to highlight savings more clearly

We A/B tested each iteration to validate our hypotheses.

The goal wasn’t to hide the fee, it was to make it feel like part of the service, and not like that last-minute penalty it felt like before.

Impact

The biggest win? Silence.
Complaints about shipping dropped by 36% in the post-purchase survey, the clearest sign that friction was fading and trust was returning.

The data backed it up:
+1.62% (91% Bayesian) transactions from discount repositioning.
+7.04% (100% Bayesian) transaction with “With Track & Trace.”
+1.85% (84% Bayesian) transactions with “Carefully packed & quickly shipped.

This is how we shipped (pun intended) results under real constraints.

Control vs. variant layout comparison showing how a data-driven UX designer repositioned shipping costs and discounts on the cart page.

And the tests that didn’t win?

We count those too. Across everything we run, about a quarter are clear wins, a smaller chunk prevent costly mistakes before they ship, and the rest come back flat. That’s normal, and we report all of it.

05 / WORDS FROM CLIENTS

Said it better than we could.

Lars is an exceptional UX professional with an incredible analytical approach to problem-solving.

His ability to break down complex challenges and craft intuitive, user-centered solutions backed by real data is truly impressive.

Beyond his remarkable skills, Lars is always ready to support the design community with his valuable insights and guidance, making him a trusted and inspiring figure for anyone fortunate enough to collaborate with him.

Jan MrazAtheros Intelligence Ltd

Through word of mouth, I heard that Lars creates unique designs for businesses. I shared my preferences and let myself be surprised.

My experience with Lars is that he’s very patient, thinks along with you, and is committed to delivering the best possible results to ensure client satisfaction.

I’m absolutely thrilled with the outcome, it looks professional! A beautiful design and stunning business cards. In my view, Lars is highly skilled and delivers top-quality work. I can wholeheartedly recommend him!

Caresse AntonissenInnerwork Caresse

This recommendation might be a bit biased since we’re family, but I can highly recommend Lars for CRO & UX-design projects.

My client was struggling with their website’s conversion rate, even though their SEO/SEA traffic had increased significantly. In a 1.5-hour Google Meet call, Lars provided a lot of actionable recommendations to improve conversions. He was able to clearly back up all of his tips with research and data as well. It was also evident during the call that Lars has a lot of knowledge and experience in CRO & UX-design. He really knows what he’s talking about.

If you’re looking for actionable tips to get more out of your website, I highly recommend reaching out to him.

Niels BroekzitterNiels Broekzitter Internet Marketing

Lars heeft ons als Stichting super geholpen met het uitzoeken en opnieuw opbouwen van de website

Omdat wij als vrijwilligers organisatie niet altijd de beste kennis in huis hebben was het belangrijk om de juiste kennis in huis te halen omadat de website verouderd was geraakt en niet langer gemakkelijk te onderhouden.

Na een volledige doorlichting van de website heeft Lars de pijnpunten gedefinieerd en alles gestroomlijnd zodat ook naar de toekomst toe met minimale inzet het maximale gehaald kan worden want de website is simpel en snel aan te passen.

ook zijn oude plugins en zaken die er niet meer toe deden systematisch verwijderd. Kortom een top resulaat waar we nog jaren mee vooruit kunnen!

Martijn van VlietZeekadetkorps Schiedam

“Design without evidence is just expensive wallpaper.”

06 / CONTACT

Let’s find your missing revenue.

Tell us about your site and your traffic. We’ll tell you where the opportunity is, and whether CRO is even the right move yet. No sales pitch, just a straight answer.

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Same traffic,more conversions.

01 / FOR YOU IF

CRO works in the right conditions

You have analytics implemented

You have steady traffic

Conversions are flat or falling

You want ongoing improvement

You’re open to being wrong

Not the right fit if…

02 / WHAT WE DELIVER

Proof, not guesswork.

Research that finds the leak.

A roadmap, not a wishlist.

Experiments, start to finish.

Analysis you can trust.

Lessons logged, winners shipped.

03 / HOW WE WORK

Three rules. No exceptions.

01. Start with evidence.

02. Design for outcomes.

03. prove it, don’t guess.

04 / PROOF

Small changes. Big numbers.

We had a killer deal, our users didn’t see it…

Why it mattered

The problem

We made value unmissable

Impact

No one cares about accessibility… Until you prove it works

Why it mattered

The problem

From moral choice to metric

Yes, we tested button colors

Impact

Now what?

What happened next?

Shipping costs suck, but what if they didn’t?

Why it mattered

The problem

Designing for Perception, Not Price

Impact

And the tests that didn’t win?

05 / WORDS FROM CLIENTS

Said it better than we could.

“Design without evidence is just expensive wallpaper.”

06 / CONTACT

Let’s find your missing revenue.

Same traffic,
more conversions.