Which CRO tool should I use?

I’ve been working on a few analytics tool comparison projects lately, utilising my experience across web analytics, CRO (conversion rate optimisation), and data visualisation/BI.

I thought I’d kick off a series of posts with one of the most direct and action-oriented uses of analytics: CRO.

There are so many analytics and content management tools out there these days. The field of CRO is no exception. I find that, broadly, these tools offer very similar functionality, with some important exceptions. If you are an expert in one tool – particularly on a technical level – then you should generally find it quite easy to move to using another.

The Google suite of products is now ubiquitous in digital analytics. I typically recommend that my clients work with Google Analytics, Google Tag Manager, and Google Optimize. These tools naturally integrate fantastically well together, and organisations usually have at least GA (and possibly GTM) in place to some extent. (I provide thorough analytics audits and roadmaps to get tagging right from the ground up and align to your strategy).

I always recommend looking at alternatives though, and there is a philosophical and ethical question over having one company have so much influence over your business!

Whichever tool you use, you will only get good results if you use the right expertise and processes. CRO needs to be tied to the organisational strategy, measurement framework, and hard insights to be anything more than a quick fix.

Google Optimize

  • In my mind, the lead CRO contender for most small to medium sized organisations (or even larger organisations with limited CRO and analytics resource).
  • The free version offers up to 5 active experiments or personalisations: adequate for entry- to intermediate-level CRO programmes.
  • Client-side, low latency JavaScript testing with visual editor or custom code. There are limits on script size.
  • Server side capabilities exist. For extensive testing of back-end functionality other tools may be preferred.
  • Native integration with Google Analytics & Google Ads.
  • No apparent traffic limits.

Optimize 360 (enterprise version) offers more active tests, personalisations, richer targeting, and enterprise support – but very expensive! Comparison between Optimize and Optimize 360.

Visual Website Optimizer

VWO is another favourite of mine, and one that I have used extensively over the years, particularly in my work at the charities Oxfam and WaterAid.

  • Various packages offering unlimited AB and MVT and qualitative insight tools like session recordings and heatmaps.
  • Client-side, low latency JavaScript testing with visual editor or custom code.
  • VWO FullStack offers server side capabilities.
  • Reliable, comprehensive, great value tool if suite of capabilities are used.

VWO is a good step up from Google Optimize free version without breaking the bank, and offers a unique combination of testing and qualitative analysis tools.


  • Various packages: “Specialist” includes unlimited AB and MVT and up to 50 personalisations.
  • Client-side, low latency JavaScript testing with visual editor or custom code.
  • Offers server side capability.
  • Very robust tool with few limitations and standardised pricing, though relatively expensive.
  • Highly-focused on AB and multivariate testing. Lacks VWO’s qualitative insight features.

Comparison between Convert and Google Optimize.

Great for hardcore testers who have decent developer resource.


  • On the premium end of CRO tools.
  • Various packages: client side, server side, client + server, and enterprise support all offered.
  • Visual editor for client side tests.
  • Offers robust technology, strong security & compliance, and high speed.
  • Long track record of presence in the CRO space.
  • Integration and developer requirements are relatively complex.

Great for those who want excellent site performance and enterprise support with CRO.


  • Various packages: “Business” version and above offer MVT.
  • Client-side, low latency JavaScript testing with visual editor or custom code.
  • Full-stack package offers server side capabilities.
  • Leading, established CRO tool with enterprise support packages.
  • Relatively expensive.

Decent all-rounder and leading tool, but perhaps not so compelling against others out there.

I hope you’ve found this a helpful quick summary of some leading CRO tools!

Feel free to get in touch with me if you would like to explore a CRO or analytics project in more depth.