Simon Vreeman

I am a Web Analyst at The Next Web.

TNW is a future-proof tech media company that focuses on this cross-generational group and helps them get the most out of technology by informing them through remarkable stories and insights, and by bringing them together through extraordinary events and workspaces.

Previously I worked at Valk Exclusief, part of the largest hospitality chain in the Netherlands run by the Van der Valk family, and Budeco.

At TNW I make sure we track all the behavior of our users on All tracking is done with Google Tag Manager and Google Analytics. Based on the data we collect with Google Analytics we provide insights with the team. And use the insights to make beter business decisions.

The data, and psychology, is also used to fuel experimentations on We now do about 200 A/B tests a year. By keeping the velocity high, we can fail faster, learn more and improve conversion rates quicker. We use our own open-sourced JavaScript library and Google Tag Manager for A/B testing.

A/B/n and MVT Testing with Google Tag Manager and Google Analytics

The costs for using an A/B testing tool, suchs as Optimizely or VWO, were rising without providing extra value. That is why I started developing this script at Valk Exclusief with Online Dialogue. At TNW we continued optimizing the script to make even leaner and more flexible.

If you have any ideas to make this script better, please let me know or contribute on Github.

My colleague Martijn and I wrote about it, and wrote a bit more about how we use and do A/B testing and analytics at TNW.

Articles by others I have read and liked are on my Instapaper profile.


If you double the number of experiments you do per year you’re going to double your inventiveness.

— Jeff Bezos, Founder & CEO of Amazon

The most important things are not things.

— Anthony J. D'Angelo

Learning never exhausts the mind.

— Leonardo da Vinci