Landing Pages with Poor Web Vitals, AdRoll

Card class: Cross-Channel • Category: Cross-Channel

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At a glance

A cross-channel table that joins the product and landing pages your AdRoll ads send shoppers to against your web-vitals measurement, and lists every landing page that is both slow (poor Largest Contentful Paint and related vitals) and converting below your account average. AdRoll is retargeting-first: most of your spend pays to bring a warm visitor or cart abandoner back to a specific page. If that page loads slowly, the retargeting cycle pays to deliver the click and then loses the shopper to a sluggish load before they can buy. This card finds the leak at the point it actually happens, the destination page, rather than blaming the campaign or the audience. It is where ad performance and site performance meet, and it only exists because Vortex IQ sees both the AdRoll serving layer and your web-vitals data.

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Calculation

Calculated automatically by joining your AdRoll landing-page data with your connected web-vitals measurement (CrUX field data and PageSpeed Insights). See the At a glance summary above for what the metric tracks and the worked example below for a typical reading.

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Worked example

Northfell Outfitters, a UK outdoor-gear DTC retailer on BigCommerce, runs AdRoll retargeting and prospecting that sends shoppers to product-detail pages via Dynamic Ads. A recent PDP template change added a heavy hero-video block and a third-party size-guide widget that slowed load on several pages. The join lists AdRoll landing pages by vitals and conversion rate against the account average. Window is the rolling 30 days to 19 Jun 26. Account average conversion rate on AdRoll-driven PDP sessions is 3.0%. What the pattern tells you:

1. Three PDPs are both slow and converting at well under half the account average. These are the leaks. AdRoll delivered warm, high-intent retargeting clicks (cart abandoners and recent visitors) to them, and the pages lost those shoppers before they could buy. The campaign is doing its job; the destination is failing.
2. The healthy boot page proves it is the page, not the audience. The /boots/alpine-gtx page loads in 2.0s and converts slightly above account average on the same kind of retargeting traffic. Same audience, same platform, good page, normal conversion. That contrast localises the fault to the slow pages, not to the retargeting pool.
3. The flagged pages share the new heavy template. All three slow pages use the PDP template with the hero-video block and the size-guide widget; the fast boot page predates it. That common factor points the engineering fix at the template, not at individual products.
4. The wasted cost is concentrated on the highest-traffic slow page. The 4-season tent page took 4,100 retargeting clicks at a 1.1% conversion rate; a page converting at account average would have produced far more sales from the same spend. Prioritise the fix by clicks-times-conversion-gap, not by which page is slowest in isolation.
5. The fix lives in engineering, not in the ad account. Defer or lazy-load the hero video, compress and correctly size hero images, load the size-guide widget on interaction rather than on page load, and reserve layout space to cut the CLS shift. As LCP improves toward the good band, conversion rate on retargeting traffic should climb back toward the account average.
6. Re-measure after the fix before touching budget. Do not pull spend off these products; fix the page and let the recovered conversion rate restore the ROAS. Pausing the campaign would forfeit warm demand that the page fix recaptures, and on AdRoll a paused retargeting line lets the audience pool cool while abandoners drift out of the window.

Quick sanity tests:

• Page slow + conversion well below average = genuine destination leak, fix the page.
• Page slow + conversion near average = the speed is tolerable for that product; deprioritise.
• Page fast + conversion below average = not a vitals problem; look at price, stock, or offer.
• Several flagged pages share a template = template-level fix, highest leverage.
• Conversion recovers after a vitals fix = confirmed the page was the cause.

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Sibling cards merchants should reference together

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Reconciling against AdRoll

Where to look in AdRoll’s own dashboard:

AdRoll dashboard at app.adroll.com, under Reporting, for clicks and conversions broken down by ad or product (the landing-page destination), and a web-vitals source (your real-user monitoring, CrUX field data, or Google PageSpeed Insights) for the LCP and CLS readings on those same URLs. AdRoll groups performance by campaign and ad rather than by URL, so you reconstruct the per-landing-page view from the destination URLs on the ads.

AdRoll cannot produce this card on its own. AdRoll sees the clicks it delivered and the conversions the AdRoll Pixel attributed per ad, but it has no idea how fast those landing pages load, that lives in your web-vitals measurement. The cross-channel join of AdRoll landing-page performance against web-vitals data is what Vortex IQ assembles. To reconcile manually, export AdRoll’s per-ad clicks and conversion rate and map each ad to its destination URL, pull the LCP and CLS for the same URLs from your vitals source, and the pages that are both slow and below your account-average conversion rate are the ones this card flags. Why our number may legitimately differ from a manual check: Cross-connector reconciliation: This card is inherently cross-channel, joining ad landing-page data to web-vitals measurement:

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Known limitations / merchant FAQs

Why is a slow landing page AdRoll’s problem and not just a site problem? Because AdRoll’s entire model is retargeting: it pays to bring a warm visitor or cart abandoner back to a specific page. If that page loads slowly, you have spent the CPC to deliver the click and then lost the shopper to a sluggish load before they could buy. The retargeting cycle’s whole purpose is defeated at the final step. The cost is real ad spend, which is why this sits in the AdRoll manifest, not only in a site-health report. My site passes Core Web Vitals overall, so why are pages flagged here? Site-wide averages hide page-level problems. The specific product-detail pages AdRoll Dynamic Ads target, often newer templates, image-heavy hero blocks, or pages loaded down with third-party widgets, can be much slower than your homepage or category pages that dominate the site-wide average. This card looks page by page at exactly the URLs AdRoll sends paid traffic to, which is where the money is leaking. Should I pause campaigns to the slow pages? No, fix the pages. Pausing forfeits warm, high-intent demand that a page fix would convert, and on a retargeting-first account a paused line lets the audience pool cool while abandoners drift out of the attribution window. The right order is to fix the vitals (defer heavy media, compress and size images, load third-party widgets on interaction, reserve layout space to cut layout shift), re-measure, and let the recovered conversion rate restore ROAS. Reserve any budget reduction for cases where an engineering fix is genuinely impossible in the near term. How do I prioritise which page to fix first? By impact, not by raw slowness. Rank the flagged pages by clicks multiplied by the conversion gap, so the highest-traffic, worst-converting page comes first. A page that is the slowest on the list but takes little AdRoll traffic matters less than a slightly-slower page absorbing thousands of paid retargeting clicks. Fix for recovered conversions, not for the worst single LCP number. Could ATT or the 1-day view window distort this card? Partly, on the conversion side only. Web vitals are measured on the device and are unaffected by ATT. The conversion-rate comparison uses AdRoll-Pixel-attributed conversions on the default 30-day click / 1-day view window, which ATT and the short view window can understate on iOS-heavy pages, so a page might look slightly worse-converting than it truly is. The vitals reading itself is reliable; weigh the conversion gap with the traffic’s iOS share in mind. Why combine slow load and low conversion instead of flagging on speed alone? Because speed alone over-flags. Some slow pages still convert acceptably for their product, and fixing them yields little. The card requires both poor vitals and a conversion rate well below the account average, which isolates the pages where the slowness is actually costing conversions. That keeps the list short and every entry worth an engineer’s time. How is this different from the Dynamic Ads out-of-stock card? That card catches a feed problem: ads still serving for SKUs the catalogue marks out of stock, where even a fast page cannot convert because there is nothing to buy. This card catches a speed problem: the product is available and the ad is valid, but the destination page loads too slowly to convert the click. Run them together so you do not spend an engineer’s afternoon optimising the load time of a page whose product is actually out of stock.

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Tracked live in Vortex IQ Nerve Centre

Landing Pages with Poor Web Vitals is one of hundreds of KPI pulses Vortex IQ tracks across AdRoll and 70+ other ecommerce connectors. Nerve Centre runs the detection layer; Vortex Mind investigates the cause when something moves; Ask Viq lets you interrogate any number in plain English. Start for free or book a demo to see this metric running on your own data.