Page speed is not an engineering vanity metric. Here is how to put a dollar figure on it before you ask for budget.
Everyone agrees fast sites are better. Very few teams can say what slow costs them, which is why performance work keeps losing to feature work.
Measure the real distribution
Field data from the Chrome UX Report reflects real users on real devices. Lab scores from Lighthouse are useful for diagnosis, not for estimating impact.
Segment conversion rate by load time
In GA4, build a comparison of sessions above and below your LCP threshold. In most ecommerce accounts we audit, the gap between a 2-second and a 4-second LCP is worth 8–15% of conversion rate.
Do the arithmetic
Multiply the conversion rate gap by the sessions currently falling on the wrong side, by your average order value. That number is your performance budget, and it usually justifies the work several times over.
Then fix the boring things
Oversized hero images, render-blocking third-party tags, unoptimized fonts and layout shift from late-loading banners account for most of the damage on the sites we inherit.
Working on something like this? Book a free audit and we will look at your account directly.