Core Web Vitals FAQ: Experts Share Little-Known Techniques

Last updated on Feb 7th, 2024 | 5 min

Have you ever wondered:

“Which is better for Core Web Vitals – Webflow or WordPress?”


“Do Hubspot forms affect LCP score?”

Important, yet too specific questions to easily find answers backed with real experience. 

Well, in the following lines, we gathered more of these outliers. In fact, all of the following questions were asked in the chatroom during our third webinar with Google on “Mastering LCP optimization.”


And the best part is:

90% of the questions were answered by our webinar participants. 

In other words – you are in for a treat.

You will get insights from fellow website owners and seasoned developers who experienced the same problems and found what works best for them. 

Let’s start with the first one. 

Core Web Vitals FAQ

What is more important – achieving a 90+ performance score in PageSpeed Insights or passing Core Web Vitals?

In general, CWV measures the actual experience of your visitors, whereas the PSI score is just a lab measurement that is good for testing and overall direction of your site performance.

Barry Pollard (Google): “Core Web Vitals are a better measure than Lighthouse score. The Performance score is a broad indicator of page load but may or may not be reflective of how your users experience your website!”

Achieve a 90+ PSI score and pass your Core Web Vitals automatically. Get NitroPack today →

Why do I see different results when using different speed testing tools?

You might see different results because these tools might be testing from various parts of the world, using different web browsers, and focusing on different aspects of your site's speed. Also, while some tools mimic a user visiting your site, others might look at real user data. Plus, things like internet connection, how busy your server is at the time, and third-party elements like ads can vary each time you test.

How do I deal with LCP issues when using HubSpot forms CTAs?

If you've implemented HubSpot forms directly on your homepage or on-page pop-ups, you might notice a decline in performance. This is primarily due to the multiple JavaScript files these forms load. A recommended workaround would be to shift your HubSpot forms to a dedicated page. Similarly, while HubSpot CTAs are great for tracking user metrics, they come at the cost of additional JavaScript load, which can slow down your site. The solution would be to evaluate the trade-offs between the insights you gain from these CTAs and the potential performance hit and look for alternative solutions. 

Is it possible to pass Core Web Vitals while using the Avada theme?

Yes, you can pass your Core Web Vitals using the Avada theme. One of the participants in our webinar with Google mentioned that combining Siteground with NitroPack yields some spectacular results. A NitroPack feature that was a game changer for the LCP score, especially, is the automatic WebP conversion. 


How much do CWV truly impact search engine rankings?

Content relevancy is the most important ranking factor when Google builds the SERP. However, many websites produce relevant, high-quality content. So, having good Core Web Vitals can be the differentiator that puts your page ahead. And ultimately, CWV reflect your users' perception and experience on your site. Ensuring a positive experience is vital to retaining visitors and encouraging repeated visits. 

NitroPack Insights: From our experience with clients, speed and good Core Web Vitals significantly enhance SEO efforts. This can reduce the time required for content to achieve favourable rankings by several months. 


Which platform is better performance-wise: Webflow or WordPress?

Some users claim that they've found Webflow quite challenging in terms of performance. Reports suggest that the platform tends to produce numerous CSS selectors, leading to unnecessary duplication unless managed correctly. Furthermore, Webflow is said to be harder to optimize, with some pointing out that its HTML structure isn't always set up efficiently, often resulting in a heavy Document Object Model (DOM). Conversely, WordPress, when optimized appropriately, is often reported to offer better performance and flexibility. Given these considerations, the general advice seems to lean towards using WordPress, especially when paired with the right optimization tools and practices, for those prioritizing performance.

Of course, this doesn’t mean you can’t achieve excellent performance using Webflow. It strongly depends on your use case and what website you want to build. 

Further Reading: 7 Best WordPress Plugins to Optimize Your Website in 2023 


What are next-gen image formats?

Next-gen formats are newer image types like WebP, AVIF, and JPEG XL. They offer better compression and quality than traditional formats like JPG or PNG. Definitely worth checking out for faster web performance!


How can I convert my images into WebP?

To convert images to WebP, you can easily use online tools like Squoosh or TinyPNG. However, using online tools requires you to manually replace all your images with WebP versions. If you have a WordPress site, the NitroPack plugin can automatically convert and serve your images in WebP format, making your site faster. 

Adam Silverstein (Google): “You can use the WebP Uploads* WordPress plugin for automatically generating next-gen versions of your images.” 

*WebP images will be generated only for new uploads, pre-existing imagery will not be converted to WebP format.

Further reading: Serve Images in Next-Gen Formats Easily (WordPress, OpenCart & Magento)


Are there any tools for generating critical CSS and extracting it from stylesheets? Or must this be done manually?

It depends on the tools you use. There are tons of online Critical CSS generators, but they do only that – generate CSS. They won’t set it up on your website - you must do that manually. On the other hand, NitroPack automatically grabs the CSS needed to visualize above-the-fold content, creates unique Critical CSS for every page, and inlines it. 

Further reading: Critical CSS: How to Boost Your Website's Speed and UX

What weight does the Core Web Vitals have as a ranking factor?

Core Web Vitals are part of Google's page experience signals, and while they play a role in ranking, they're not the only factor. Quality content remains key! But as user experience becomes more crucial, these vitals will likely have increased importance over time. It is always good to optimize them alongside producing top-notch content!

What will happen to my rankings if I fail LCP? Is SEO ranking demoted?

Failing LCP might negatively impact your SEO rankings since it's one of the Core Web Vitals. But remember, while it's a factor, it's not the ONLY factor. There are many other aspects to SEO. Also, although important, SEO isn’t the only way to success. You still need to guarantee the perfect user experience for all the visitors that land on your page. Put simply, passing your Core Web Vitals has a greater value than just SERP positions.   

How do I identify which element is considered for LCP?

You can use Chrome's DevTools. Open it up, go to the 'Performance' tab, and record a page load. In the results, there'll be a section called 'Timings', and you'll see an 'LCP' marker. Click on it, and it'll highlight the element considered for LCP on your page in the Summary tab. Super useful for pinpointing what's causing slowdowns! 

Chrome DevTools


My page loads are “poor" by grade. My host tried to upgrade me, does MySQL 5.7 matter?

Upgrading MySQL can help with database performance, but if your page load grades are poor, there might be other factors at play. MySQL 5.7 does have improvements over older versions, but for front-end speed, you'd want to look at things like caching, image optimization, and reducing scripts. Your hosting environment does matter, but it's just one piece of the puzzle. Consider also checking other elements affecting your load time!

Further reading: How Your Hosting Provider Impacts Your Site's Performance


Step Up Your Core Web Vitals Game

These questions are only a fraction of what happened during our “Core Web Vitals for Business” webinar series with Google. 

NitroPack Core Web Vitals for Business webinar series

If you want to discover more web performance optimization gems, you should rewatch all of the available episodes:

Or you could bookmark our dedicated Core Web Vitals materials:

Niko Kaleev
Web Performance Geek

Niko has 5+ years of experience turning those “it’s too technical for me” topics into “I can’t believe I get it” content pieces. He specializes in dissecting nuanced topics like Core Web Vitals, web performance metrics, and site speed optimization techniques. When he’s taking a breather from researching his next content piece, you’ll find him deep into the latest performance news.