Performance

Core Web Vitals Checker

Core Web Vitals Checker reads a Lighthouse or PageSpeed JSON report in your browser to show category scores and Core Web Vitals.

Client-sideRuns in your browser — paste or load your data and it is processed locally; nothing is uploaded.

Core Web Vitals Checker is a free Performance utility that runs entirely in your browser — nothing you enter is uploaded.

Core Web Vitals Checker

Core Web Vitals Checker reads a Lighthouse or PageSpeed JSON report in your browser to show category scores and Core Web Vitals.

How to use Core Web Vitals Checker

  1. Give Core Web Vitals Checker a Lighthouse JSON report (or paste it) to work from.
  2. Press Read report to run it locally in your browser.
  3. Use the category scores and Core Web Vitals Core Web Vitals Checker produces — nothing was uploaded.

About this tool

Core Web Vitals Checker runs entirely in your browser. Export a report from Chrome DevTools or PageSpeed Insights and load the JSON into Core Web Vitals Checker to see the scores locally.

Because Core Web Vitals Checker parses a report you provide, the results match whatever run you exported. It behaves the same on desktop and mobile, with nothing stored remotely.

Frequently asked questions

How do I use Core Web Vitals Checker?

Core Web Vitals Checker lets you check your input right in the browser, with the result shown instantly and nothing uploaded.

Do I need an account for Core Web Vitals Checker?

No — Core Web Vitals Checker needs no account, sign-up or installation.

Does Core Web Vitals Checker upload my data?

No — Core Web Vitals Checker processes everything locally in your browser, so nothing you enter is uploaded or stored.

What file does Core Web Vitals Checker read?

Export a Lighthouse or PageSpeed Insights JSON report and load it into Core Web Vitals Checker; it surfaces the scores and Core Web Vitals locally.

Does Core Web Vitals Checker work on mobile?

Yes — Core Web Vitals Checker is just a web page and runs on any modern browser, including phones and tablets.

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