Updated 9th September 2026
Core Web Vitals: Guide for website owners & marketers
People expect websites to load quickly, respond fast, and not jump around while they’re reading - and these are exactly the things your Core Web Vitals measure.
Google introduced these key performance measures in May 2020 as a way of checking how smooth and user-friendly a website is. Perform well and it can help you rank higher on Google while giving visitors a better experience. Perform badly and users get a slow, unstable site that frustrates them into leaving - increasing bounce rate and reducing conversions.
What are Core Web Vitals?
Core Web Vitals are three key measurements Google uses to judge whether your website is fast and user-friendly:
- Largest Contentful Paint (LCP) - how long the main content on a page takes to load.
- Interaction to Next Paint (INP) - how quickly your site responds when someone clicks a button or types something (this replaced the older First Input Delay metric).
- Cumulative Layout Shift (CLS) - how stable the page is. If a user goes to tap a button and the page shifts so they hit something else by mistake, that’s the problem CLS measures.
Why are Core Web Vitals important?
Better user experience
People expect websites to be fast and smooth. If a site takes too long to load or shifts around while they’re using it, they’ll leave - and a website with strong Core Web Vitals is far more likely to keep visitors happy, engaged and moving towards a conversion.
Helps with SEO & Google rankings
Google ranks websites based on how useful they are, and a slow or difficult site works against you. Improving your Core Web Vitals improves your chances of showing up higher in the search results.
Improves PPC performance
If you run paid ads, a slow website can quietly cost you money. Google prioritises fast-loading landing pages, so slow ones can make it harder to appear for key searches and push up what you pay per click.
How can I check my Core Web Vitals?
Three free tools will tell you how your website is performing:
What do the results mean?
Results come back in three colours, traffic-light style. Green means your website is fast and user-friendly. Orange means something is slowing your site down, but it’s fixable. Red means your site has serious issues that need urgent attention.
Common fixes for Core Web Vitals issues
If your website isn’t performing well, the good news is that most fixes are well understood.
To speed up LCP, start with your images - compressing large files is usually the single biggest win. Fast, reliable hosting matters too, as does trimming any unnecessary content that’s weighing the page down.
To fix INP, look at what’s competing for the browser’s attention. Heavy animations and stacked pop-ups make a site feel sluggish, as do unnecessary code and third-party scripts like extra widgets. Stripping these back, and using caching to store data, helps your site respond the moment someone interacts with it.
To reduce CLS, give everything a fixed home. Set defined sizes for images and videos so nothing suddenly resizes as it loads, avoid ads or banners that push content around unexpectedly, and test your site on different devices to check it stays stable everywhere.
Summary
Core Web Vitals are just Google’s measure, but improving them makes your website better for real people. A faster, more stable site earns better search rankings, keeps visitors engaged for longer, lowers your ad costs, and delivers the smooth browsing experience users now expect as standard.
Check in on your scores regularly - especially after updates or design changes - and your website will stay competitive in the search results while giving every visitor a positive experience.
Need help improving your website’s performance? Get in touch with the experienced website team at Atelier.
FAQs
What are Core Web Vitals?
Three measures of website performance: LCP (page load speed), INP (how quickly the site responds to clicks) and CLS (page stability, preventing content from shifting around).
Why do they matter for SEO?
Google ranks fast, user-friendly sites higher in the search results, so strong Core Web Vitals support your visibility.
How do they affect PPC?
Slow landing pages cost more per click and can reduce how often your ads appear for key searches.
How can I check Core Web Vitals?
Use Google PageSpeed Insights, Google Search Console or Lighthouse - all three are free.
What do the results mean?
Green is good, orange needs improvement, and red means serious issues that should be fixed urgently.
How can I improve Core Web Vitals?
Compress images and use fast hosting for LCP, cut pop-ups and unused code for INP, and set fixed sizes for images and videos for CLS.
How often should I check Core Web Vitals?
Regularly - and always after site updates or design changes, since these are when scores most often slip.
