Core Web Vitals are Google's standardised metrics for measuring real-world user experience. They became ranking signals in 2021 and have grown in importance since. The good news for Wix users is that Wix has invested heavily in improving default Core Web Vitals performance, but there is still work to do on your end.
Largest Contentful Paint (LCP)
LCP measures how long it takes for the largest visible element on the page to load, usually a hero image or large heading. Google's threshold is: Good = under 2.5 seconds, Needs Improvement = 2.5 to 4 seconds, Poor = over 4 seconds.
On Wix sites, LCP is most commonly hurt by large, unoptimised hero images. Wix automatically serves images in WebP format and provides responsive images, but if you upload a 5MB hero image, even Wix's compression will not fully compensate.
Fix LCP on Wix
Before uploading any hero image to Wix, compress it to under 200KB using Squoosh (squoosh.app). Use a JPEG or WebP file at no wider than 1400px. This single change typically moves LCP from Poor to Good on most Wix sites.
Cumulative Layout Shift (CLS)
CLS measures visual stability, how much the page layout shifts unexpectedly as it loads. A CLS score of 0.1 or below is considered Good. Layout shifts frustrate users (accidentally tapping the wrong button) and Google penalises sites with high CLS.
Common CLS causes on Wix: images without defined dimensions, fonts loading late causing text reflow, and third-party widgets (chat bots, cookie banners) inserting themselves into the layout.
Interaction to Next Paint (INP)
INP replaced First Input Delay (FID) as a Core Web Vital in March 2024. It measures the responsiveness of all user interactions on a page, not just the first. Good INP is under 200ms. On Wix, INP is most affected by heavy JavaScript from third-party apps and marketing scripts loaded in the page header.
How to check and improve your Core Web Vitals on Wix
- 1Go to Google Search Console and open the Core Web Vitals report
- 2Identify which pages are failing and which metric they are failing on
- 3Run failing pages through PageSpeed Insights (pagespeed.web.dev) for specific recommendations
- 4Fix LCP: compress hero images before upload, enable lazy loading for below-fold images
- 5Fix CLS: add explicit width and height to all images in the Wix editor
- 6Fix INP: remove unused third-party apps from the Wix App Market, defer non-critical scripts
Complete How-To Guide: Measuring and Fixing Core Web Vitals on Your Wix Site
This guide takes you through the complete process of checking your Wix site's Core Web Vitals scores, identifying the specific issues causing poor performance, and implementing the fixes that will move your metrics from red to green.
Follow these steps to measure and fix Core Web Vitals on your Wix site
- 1Open Google PageSpeed Insights at pagespeed.web.dev and enter your homepage URL, then run the test for both Mobile and Desktop
- 2Note your LCP, CLS and INP scores and whether each is Good (green), Needs Improvement (amber), or Poor (red)
- 3Open Google Search Console and navigate to the Core Web Vitals report to see which pages across your site are failing and on which metric
- 4For LCP issues: identify your largest above-the-fold element (usually a hero image), compress it to under 200KB using squoosh.app, and re-upload it to Wix in WebP format at no wider than 1400px
- 5For LCP issues: remove any unnecessary Wix apps or third-party scripts that delay page rendering by going to Wix Dashboard > Apps and uninstalling anything you do not actively use
- 6For CLS issues: go to the Wix editor and ensure every image has explicit width and height dimensions set, and avoid using auto-sizing containers for above-the-fold content
- 7For CLS issues: check that your web fonts load correctly by using Wix system fonts or ensuring custom fonts are preloaded, preventing text reflow
- 8For INP issues: audit all third-party apps and marketing scripts on your Wix site, removing or deferring any that add heavy JavaScript to every page
- 9For INP issues: simplify complex page animations and hover effects in the Wix editor, especially on mobile where processing power is limited
- 10Re-run PageSpeed Insights after each round of fixes to measure improvement, focusing on the field data (real user data) rather than just lab data
- 11Submit any fixed pages for re-indexing in Google Search Console using the URL Inspection tool
- 12Set up a monthly check of the Core Web Vitals report in GSC and PageSpeed Insights to catch any regressions early
Final Checkpoint
All three Core Web Vitals metrics (LCP, CLS, INP) should show green (Good) in PageSpeed Insights for both mobile and desktop. If any metric is still amber or red, focus on the single largest contributor identified in the Diagnostics section of the PageSpeed report.
Essential Resources
Google PageSpeed Insights
Test page speed and Core Web Vitals scores for any URL on mobile and desktop
Google Search Console Core Web Vitals
Monitor which pages pass or fail Core Web Vitals using real user data
Squoosh
Google's free browser-based image compressor for optimising images before uploading to Wix
Web Vitals Chrome Extension
Real-time Core Web Vitals monitoring while browsing your Wix site
GTmetrix
Detailed speed testing with waterfall charts showing which resources delay page load
