Page speed is a business metric, not a technical vanity. Every extra second of load time costs you visitors, rankings, and revenue.
Google defines the user experience of loading a page through three signals called Core Web Vitals. Understanding them is the first step to a faster site.
## Largest Contentful Paint (LCP)
LCP measures how quickly the main content of a page becomes visible. A good score is under 2.5 seconds. The most common culprits are large hero images, render-blocking scripts, and slow servers.
## First Input Delay (FID) and Interaction to Next Paint (INP)
These measure responsiveness — how quickly the page reacts when a visitor clicks or taps. Heavy JavaScript and inefficient event handlers are usually the cause of poor scores.
## Cumulative Layout Shift (CLS)
CLS measures visual stability — whether elements jump around as the page loads. Images without dimensions, injected ads, and late-loading fonts are the usual offenders.
## Speed is conversion
Studies consistently show that faster pages convert better. When a page feels instant, trust goes up and bounce rates go down. Speed is not a developer concern — it is a commercial advantage.
## Where to start
Measure first. Run a Lighthouse report or check PageSpeed Insights, fix the biggest offenders in order of impact, and re-measure. Most sites see meaningful improvement within a week of focused work.
