Page Speed Audit: See How Load Time Is Costing You Conversions

What a page speed audit actually measures

A page speed audit answers one question: how much of your traffic leaves before the page is usable. It is not a technical scorecard for its own sake. The metrics that matter are the ones Google standardized as Core Web Vitals, because they were chosen specifically to approximate what a visitor experiences rather than what a server does.

Google's guidance adds a detail people skip: you should measure at the 75th percentile of page loads, segmented across mobile and desktop. That is deliberate. Averages hide the tail, and the tail is where you lose people. If your median LCP is 1.8 seconds and your 75th percentile is 5.2 seconds, a quarter of your visitors are having an experience your dashboard never shows you.

How slow is slow enough to matter

The honest framing is that page speed is a threshold problem, not a linear one. Shaving 200 milliseconds off a page that already loads in 1.4 seconds is unlikely to change anything a business would notice. Moving a page from 6 seconds to 2.5 seconds is a different category of change, because you are crossing the point at which people abandon.

This is why we treat speed as one line in a prioritized list rather than the headline finding. On most landing pages we audit, speed is not the biggest leak. A vague headline, a CTA that does not say what happens next, or a form asking for nine fields will usually cost more conversions than a second of load time. But when speed is the problem, it is often the single largest one, and it is invisible to anyone reviewing the page on a fast office connection.

Why mobile is where the damage happens

Almost every speed problem we see is a mobile problem that looks fine on desktop. The page is tested on a laptop on office wifi, loads in under two seconds, and gets signed off. The same page on a mid-range Android phone on a congested cellular connection takes four times as long, because the device has less CPU to parse JavaScript and the network has more latency on every request.

Three causes account for most of it. Uncompressed hero images shipped at desktop dimensions and scaled down in CSS. Render-blocking JavaScript, usually from tag managers, chat widgets, and analytics scripts that load before the content. And web fonts that hold text invisible until they finish downloading. None of these require a rebuild to fix, which is the useful part.

What to fix first, in order

The order below is roughly by effort-to-impact ratio, highest first, and it is what our audit prioritizes toward.

Notice that the first four are all low effort. In practice a page that is failing Core Web Vitals can usually be pulled back into the good range without a developer touching the application code, which is why speed is worth checking before you plan a redesign around it.

How much does page speed affect conversion rate?

Enough to matter, and less than the case studies suggest. You will find a lot of confident percentages circulating, and most trace back to a handful of studies on very large ecommerce sites where a fraction of a percent is worth millions. Those numbers do not transfer cleanly to a B2B landing page doing 8,000 visits a month.

What holds up across contexts is directional and simple: slower pages convert worse, the effect gets sharply worse past roughly three seconds, and the damage is concentrated on mobile and on first-time visitors who have no cached assets and no reason to wait. We show load time as one weighted factor in the audit score rather than attaching a promised lift to it, because the honest version of this is a factor to weigh, not a formula.

Does page speed affect SEO too?

Yes, but less than the amount of writing on the subject implies. Core Web Vitals are a confirmed ranking signal, and they are a tiebreaker rather than a primary factor. A fast page with thin content will not outrank a slow page that answers the query properly. What speed reliably does is protect the traffic you already earn, because a visitor who bounces before render counts as a lost conversion regardless of what position sent them.

Where the speed read sits in a Converto audit

Converto reads the live page you already have and returns load time as one line in the same 0 to 100 conversion score as the copy, layout, and CTA findings. There is nothing to install and no snippet. That matters because the alternative is running a speed tool, a heatmap tool, and a copy review separately, then trying to decide across three dashboards which fix to do first.

If speed is the leak, you will see it ranked against everything else. If it is not, you will see that too, which saves you a week of image optimization on a page whose real problem is the offer. The full check is on the landing page audit page, the scoring model is explained under the landing page grader, and if you want the numbers behind the abandonment threshold, our post on landing page load time goes deeper. Suggestions are data-informed, not guarantees.