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Honest VWO Review: The Good, The Bad, The Ugly (2024)

Donald Ng
January 10, 2024
5-star rating
Reviews on Capterra

When it comes to researching a new product, one effective tactic is to ask both the brand itself and its competitors for their honest opinions. This approach sheds light on the strengths and weaknesses of each brand, helping you make an informed decision. 

In that spirit, we're here to provide a brutally honest review of VWO, a leading A/B testing tool. Unlike generic and biased reviews, we'll delve into the details that others might shy away from.

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The Good

VWO boasts several key strengths that have made it a top contender in the A/B testing market:

1. Free plan for up to 50,000 monthly tested users

VWO's generous free plan caters to small and medium-sized websites, offering essential features like A/B tests, multivariate tests, and basic segmentation.

2. Complete optimization suite (when you pay)

For those who outgrow the free plan, VWO offers a very complete paid tool. It includes advanced features like heatmaps, session recordings, funnel tests, server-side testing, and more.

So, if you can afford it, VWO provides an all-in-one optimization suite.

3. Established company with a solid track record

VWO is one of the pioneers in the A/B testing space, founded in 2008. Over 300,000 users trust VWO to optimize their websites and apps.

They have a long track record of serving customers and their experience shows in the polished product they’ve built.

So, those are some of the best aspects of VWO. It offers a lot for free users and has the capabilities to handle advanced needs if you’re willing to pay.

The Bad

Despite its strengths, VWO does come with its fair share of downsides:

1. Cumulative Layout Shift (CLS) problems

VWO's approach to page loading can lead to Cumulative Layout Shift issues, which Google now penalizes

While VWO prioritizes speed to give the illusion of quick loading, this can result in a noticeable shift in the layout of the page, compromising user experience.

2. Slow variation loading times

The loading times for variations in VWO can be slower compared to other tools. Their SmartCode can take an additional 2-3 seconds to load test changes, contributing to slower overall page loading times and potential CLS penalties.

Here is a 5-min video explaining how VWO might affect your website speed performance.

3. Expensive pricing model

While VWO's free plan is appealing, costs can escalate quickly once you surpass 50,000 monthly users. Advanced features, such as segmentation filters, require additional fees, and enterprise plans are necessary for websites with over 50,000 users. 

Add-ons like heatmaps and server-side testing also come at an extra cost, making the minimum yearly contract starting at $24,000 for more advanced capabilities.

4. High carbon emissions

Surprisingly, VWO's software produces a significant environmental impact due to the carbon emissions generated by the code running each test. Installing VWO alone results in 0.04g of CO2 per page view, amounting to 2kg per month for a site with 50,000 monthly visitors.

In the face of climate change, this carbon footprint raises concerns when compared to other tools that have optimized their emissions.

The Ugly

Beyond its product features, VWO's business practices have attracted criticism from users who experienced less-than-pleasant encounters:

1. Sales bureaucracy

Customers have voiced frustrations about VWO's complexities and lack of transparency in their pricing and sales process.

Requesting upgrades or setting up new accounts often involves numerous steps, including Zoom meetings with sales representatives, proposals with high prices, and unnecessary tier upgrades.

2. Unethical upselling practices

Numerous customers have expressed disillusionment with VWO's policies regarding feature upgrades.

Some have reported purchasing plans specifically for certain features, only to find out that those features were relocated to more expensive tiers.

Instead of a simple upgrade, customers are forced to purchase entirely new plans without being allowed to use any remaining balance from their initial plans.

The Alternative

If you're seeking an alternative to VWO that addresses its weaknesses head-on while offering unique features and advantages, look no further than Mida:

1. No CLS issues

Mida stands out by avoiding Cumulative Layout Shift problems. It ensures that page content is only displayed once variations are loaded, leading to a better user experience and compliance with Google guidelines.

2. Faster variation loading

Through optimized SmartCode, Mida can load variations almost instantly, resulting in quicker page loading times with minimal delays. 

Compared to VWO's 2-3 second load times, Mida ensures pages display in under 500ms.

3. Lowest carbon emissions

Mida places a strong emphasis on sustainability, employing lightweight code and energy-efficient servers.

As a result, it produces negligible CO2 emissions per test, setting a new standard for eco-friendly software.

Learn about Mida’s low carbon footprint.

4. Honest and transparent pricing

With Mida, pricing is straightforward and transparent. All pricing tiers are clearly published on their website, eliminating the need for complex enterprise quotes or extensive demos.

Simply choose the tier that best suits your needs as you grow.

Learn more about Mida unlimited, usage-based pricing model.

5. Forever free up to 50,000 users

Similar to VWO, Mida offers a forever free plan for up to 50,000 monthly tested visitors. There's no pressure to upgrade until it becomes absolutely necessary.


In conclusion, VWO has established itself as a leader in A/B testing tools with notable strengths. However, it is essential to recognize its weaknesses and consider alternatives such as Mida, which offers superior performance in critical areas.

While no tool is perfect, competition fosters innovation. By embracing newer players like Mida and continually improving their own offerings, VWO may address its weaknesses and provide an even better experience for users.

In your quest to find the ideal testing platform, carefully weigh the pros and cons highlighted in this brutally honest review. Remember to conduct thorough research, compare tools, and make an informed decision based on your specific needs.

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