Core Web Vitals are a set of performance metrics Google uses to measure whether your website delivers a genuinely good experience to real users. They became part of Google's page experience ranking signals in 2021, Interaction to Next Paint replaced First Input Delay in March 2024, and the thresholds have not changed since. In 2026 they remain one of the clearest technical SEO levers available to local business owners who want to compete more effectively in Denver search.
This guide explains what each metric means in plain language, how to check your scores, and — most importantly — which fixes deliver the biggest improvement for the kinds of websites most Denver local businesses are running.
What Core Web Vitals Actually Measure
The three Core Web Vitals each measure a different dimension of page experience:
Largest Contentful Paint (LCP) — Loading Performance
LCP measures how long it takes for the largest visible content element on your page to fully render. Usually this is your hero image or main headline. Google considers under 2.5 seconds "good," 2.5 to 4 seconds "needs improvement," and over 4 seconds "poor."
For most local business websites, LCP is the primary problem. An unoptimized hero image measured in megabytes rather than kilobytes can add several seconds to load time on a mobile connection by itself.
Interaction to Next Paint (INP) — Responsiveness
INP replaced First Input Delay (FID) in March 2024. It measures how responsive your page is to user interactions — tapping buttons, clicking links, opening menus. 200ms or less is good. Between 200 and 500ms needs improvement. Over 500ms is poor.
INP problems are most common on sites with heavy JavaScript — complex animations, multiple chat widgets, large ad libraries, or bloated page builders. For simple local business sites, INP is rarely the primary issue.
Cumulative Layout Shift (CLS) — Visual Stability
CLS measures how much your page content moves around as it loads. That frustrating experience of tapping a link and having it jump away because an image loaded above it — that's CLS. A score of 0.1 or below is good. Over 0.25 is poor.
Common CLS causes: images without specified dimensions, web fonts that cause text reflow as they load, and ad or embed scripts that push content down when they render.
How to check your scores: Go to pagespeed.web.dev and enter your URL. Always check the Mobile tab — mobile scores are what matter for local SEO since most local searches happen on phones. Your mobile score is usually lower than your desktop score. If your site gets enough traffic, the box at the top shows field data from real Chrome visitors over the last 28 days; that is the Core Web Vitals result, and the 0 to 100 score underneath is a lab test for diagnosing problems. For a worked example, you can run Lighthouse on eyetoad.com and compare.
Why Mobile Scores Are What Matter
Google uses mobile-first indexing — meaning it primarily evaluates your site's mobile version for ranking purposes. And the reality is that most local service searches in Denver happen on mobile devices, often on cellular connections that are slower than home WiFi. The gap between your desktop score and mobile score can be enormous, and it's the mobile score that drives both rankings and real-world conversion performance.
Many Denver business owners check their site on their office WiFi, see it loads quickly, and conclude there's no speed problem. Check it on your phone using cellular data and you'll often see a completely different experience.
The Fixes That Move the Needle Most
Fix 1: Optimize Every Image
This is the single highest-impact fix for the majority of local business websites. Steps: compress all images using a tool like Squoosh.app or TinyPNG, convert them to WebP format (significantly smaller file size with negligible quality difference), and add explicit width and height attributes to all img tags so the browser knows the layout before images load (prevents CLS).
Fix 2: Add Lazy Loading to Off-Screen Images
Adding loading="lazy" to image tags below the fold tells the browser not to load those images until the user scrolls toward them. This dramatically reduces the initial page weight and improves LCP on image-heavy pages.
Fix 3: Audit and Trim Third-Party Scripts
Go through every script running on your website. Chat widgets, review badges, heatmap tools, multiple analytics platforms, Facebook pixels, Google Tag Manager with a dozen tags inside it — each one adds load time. Remove anything you don't actively use and monitor. Consolidate where possible.
Fix 4: Enable Browser Caching and Use a CDN
Cloudflare's free tier provides CDN (serving files from servers near your visitors), aggressive caching, and image optimization for any website. Setup is usually quick and can meaningfully improve load times for visitors across Denver and beyond.
Fix 5: Upgrade Hosting If TTFB Is High
Time to First Byte (TTFB) is how long your server takes to begin responding to a request. If it's consistently over 800ms, no front-end optimization will fully compensate. Managed WordPress hosts like Kinsta or WP Engine often deliver much better TTFB than generic shared hosting. Google's own guidance treats 0.8 seconds or less as a good TTFB.
Priority order: Tackle images first — it's the fastest win with the biggest impact. Then audit scripts. Then evaluate hosting. In most cases, images alone move the needle enough to see a meaningful score improvement. Don't get paralyzed trying to fix everything at once.
Keeping It in Perspective
Core Web Vitals are one factor in a complex ranking algorithm. Excellent scores won't overcome weak content or a thin backlink profile. But poor scores create a ceiling on how well even strong content can perform — and in competitive Denver markets where multiple businesses have comparable authority, technical performance can be the deciding factor.
More practically: slow sites lose conversions. Even if you rank well, every second of additional load time is filtering out a percentage of visitors who would have called you if your page had loaded faster.
If you want a free technical audit of your Denver business website — including Core Web Vitals scores, structured data, mobile experience, and conversion readiness — contact Eye To Ad Media. We'll give you a clear picture of what's holding your site back and the specific fixes to prioritize.
Questions readers ask
Are Core Web Vitals a ranking factor in 2026?
Yes. They are part of the page experience signals Google's ranking systems use. Google is also clear that a good page experience does not override relevance: a fast page with a weak answer will not outrank a slower page that answers the search better.
What are the current Core Web Vitals thresholds?
Largest Contentful Paint of 2.5 seconds or less, Interaction to Next Paint of 200 milliseconds or less, and Cumulative Layout Shift of 0.1 or less. A page passes when at least 75 percent of real visits meet all three, measured separately for mobile and desktop. The thresholds have not changed since INP was added in 2024.
Why is my PageSpeed score different from my Core Web Vitals result?
The 0 to 100 performance score is a Lighthouse lab test of one simulated page load. The Core Web Vitals assessment at the top of PageSpeed Insights is field data from real Chrome users over the previous 28 days. The field data is what reflects your visitors; the lab score is for finding what to fix.
What replaced First Input Delay?
Interaction to Next Paint replaced First Input Delay as a Core Web Vital on March 12, 2024. FID only timed the first interaction on a page; INP looks at how quickly the page responds to taps, clicks and key presses throughout the visit.
Which Core Web Vitals fix should a local business make first?
On most local business sites it is images: compress them, serve WebP or AVIF, and give every image a width and height. That usually improves Largest Contentful Paint and layout shift at the same time. Third-party scripts and slow hosting come next.