The three metrics that matter
Core Web Vitals are Google's measurable stand-ins for how fast and stable a page feels to a real user. There are three: LCP (how quickly the main content loads), INP (how fast the page responds when you tap or click), and CLS (how much the layout jumps around while loading).
Google reports these two ways — lab data from tools like Lighthouse, and field data from real Chrome users. Field data is what actually influences rankings, so that's where we start.
- LCP (Largest Contentful Paint) — target under 2.5 seconds
- INP (Interaction to Next Paint) — target under 200 milliseconds
- CLS (Cumulative Layout Shift) — target under 0.1
- Field data (real users) separated from lab data (synthetic tests)
- Mobile and desktop assessed separately, since scores differ
Finding the real bottleneck
A page-speed score is a symptom, not a diagnosis. Slow LCP might be a huge unoptimized hero image, a slow server response, or render-blocking CSS. Poor INP is usually heavy JavaScript tying up the main thread. CLS is almost always images or ads without reserved space, or fonts that swap in late.
We trace each failing metric to its actual cause using waterfall and performance-trace data, so the fixes target the real bottleneck instead of guessing.
- Trace slow LCP to server response, render-blocking resources, or heavy images
- Find the scripts and third-party tags inflating INP and main-thread work
- Identify layout shifts from unsized images, ads, or late-loading fonts
- Spot oversized, unoptimized, or wrong-format images
- Measure the real cost of third-party embeds, chat widgets, and trackers
Fixes that actually move the numbers
The point of the audit is a prioritized fix list — the changes that will move your scores the most for the least effort, in plain terms your developer can act on.
Common wins are compressing and correctly sizing images, serving modern formats, deferring non-critical JavaScript, reserving space for anything that loads late, and improving server or hosting response time.
- Compress, resize, and convert images to modern formats (WebP/AVIF)
- Defer or split heavy JavaScript and remove unused code
- Reserve explicit dimensions for images, embeds, and ad slots
- Preload critical fonts and set font-display to avoid shift
- Reduce or lazy-load third-party scripts and improve server response time
- Add caching and a CDN where it makes sense
More on seo audits
Frequently asked questions
Do Core Web Vitals actually affect my rankings?
They're a real but modest ranking factor — part of Google's page-experience signals. They rarely outweigh strong, relevant content, but between two comparable pages, the faster, more stable one has an edge. The bigger payoff is often user experience: faster pages keep more visitors and convert better.
My Lighthouse score is 95 but Google says I'm failing — why?
Lighthouse is a lab test on a simulated device and connection. Google's ranking assessment uses field data from real Chrome users on real devices and networks, which is almost always slower and more varied. When they disagree, the field data is the one that counts for rankings.
Can you fix these or just find them?
We diagnose and prioritize the issues, and we can implement the fixes too — image and code optimization, caching, template changes. Some fixes are quick; others depend on your platform, theme, or hosting. We'll tell you honestly which is which before any work starts.