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Core Web Vitals

The Core Web Vitals Insight Hub gives publishers the tools to track and analyse Core Web Vital data over time through clear graphical views.

What are Core Web Vitals (CWV)?

Core Web Vitals (CWV) are a set of user-centred performance metrics that measure key aspects of a website's experience: how quickly a page loads, how responsive it is, and how stable the content is. The aim is to ensure an engaging and enjoyable user experience.

For publishers in the ad industry, CWVs are crucial as they can directly impact both user experience and search engine rankings, both key factors in driving traffic and maximising revenue. The longer publishers can keep users engaged on their site, the more likely they are to see and interact with more ads.

Fusion tracks these important values on every page load, providing publishers with accurate, actionable insights to enhance site performance and maximise revenue.

Metrics we check

  • Cumulative Layout Shift (CLS)

    CLS tracks how much a web page's content unexpectedly shifts while loading. Unexpected movement of a page’s content can disrupt the user experience and lead to annoying and sometimes damaging misclicks. A low CLS indicates a stable page layout, enhancing user satisfaction and trust, and leading to longer site visits.

  • Largest Contentful Paint (LCP)

    LCP reports the time it takes for the largest visible image, video, or text block to render in the viewport when a user first navigates to the page. Quicker load times can create a positive first impression and increase engagement, reducing bounce rates from users.

  • Interaction to Next Paint (INP)

    INP assesses a page’s overall responsiveness by measuring how quickly it responds to user interactions, such as clicks, taps, and keyboard inputs, throughout the user’s visit. The final INP value is determined by the longest interaction found, ignoring outliers.

    The less a page lags and the quicker it responds to user interactions, the less frustration there is. This increases the chances of longer engagement and the likelihood of ad viewability and interaction.

  • First Contentful Paint (FCP) FCP is the measurement of how quickly the first piece of content (text or images) appears on the screen when the page starts loading.

    A quick FCP increases the perceived reliability with the site and reassures users that the page is loading. Both factors likely increase the chances that users will stay and potentially see and interact with ads.

Each graph provides benchmark line indicators for both good and poor to represent the healthy ranges. This allows publishers to monitor performance over time and compare it against industry recommendations.

Additional Insights

Layered on top of each CWV metric, Fusion offers insights into how the absence of header bidding, execution, and ad requests may impact performance, helping publishers understand how ad serving can influence their Core Web Vitals.

Date Filtering

Using the date filter functionality, the results can be tailored to display data over a range of preset or custom date ranges, allowing for more precise analysis.

Useful Resources