Core Web Vitals | Speed
Core Web Vitals checker for practical website QA.
In one line: a plain-language checklist for the speed metrics Google actually measures — on a real phone, on a real network, without the jargon.
Speed work can become technical fast. Start with what humans feel: loading, jumping, waiting and frustration.
Questions people ask
What are Core Web Vitals?
Google's speed and stability metrics measuring real user experience: loading (LCP), interactivity (INP) and layout shift (CLS).
Why does my site feel slow despite good scores?
Lab scores simulate one visit on one device; your real customers arrive on older phones and weaker networks. Field data - what real users experienced - is the truth that matters.
Is a perfect 100 score necessary?
No. Green field metrics for real users matter more than a lab 100. Chasing the last few lab points often adds risk for no visible gain.
Practical checks
- Hero image is compressed and sized correctly.
- No layout jumps when fonts, banners or forms load.
- Buttons respond quickly on mobile.
- Unused scripts are removed or delayed.
- Images below the fold lazy-load.
- Forms work on Android, iOS and desktop browsers.
- Pages have one clear H1 and readable tap targets.
Next step
Use this as a human QA pass, then confirm with PageSpeed Insights, Lighthouse and Search Console field data.
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