How to use Web Speed Test Online
- Give Web Speed Test Online a Lighthouse JSON report (or paste it) to work from.
- Press Read report to run it locally in your browser.
- Read the category scores and Core Web Vitals that Web Speed Test Online lays out for you.
About this tool
There is no server behind Web Speed Test Online. Web Speed Test Online reads a Lighthouse or PageSpeed Insights JSON report in your browser and surfaces the headline numbers without a server.
Because Web Speed Test Online parses a report you provide, the results match whatever run you exported. Nothing you enter is uploaded, and it keeps working offline once the page has loaded.
Frequently asked questions
How do I use Web Speed Test Online?
Use Web Speed Test Online to check your input without installing anything; everything happens client-side.
Does Web Speed Test Online cost anything?
No — Web Speed Test Online is completely free, with no sign-up and no hidden limits.
Where is my data processed by Web Speed Test Online?
Entirely in your browser — Web Speed Test Online keeps your data on your own machine and sends nothing anywhere.
What file does Web Speed Test Online read?
Export a Lighthouse or PageSpeed Insights JSON report and load it into Web Speed Test Online; it surfaces the scores and Core Web Vitals locally.
Does Web Speed Test Online work on mobile?
Yes — Web Speed Test Online is just a web page and runs on any modern browser, including phones and tablets.