How to use Page Size Checker
- Generate a Lighthouse/PageSpeed JSON report and paste it into Page Size Checker.
- Page Size Checker reads it locally and surfaces total transfer size, per-type resource weight and gzip/Brotli compression savings.
- Read off the largest resources and compression opportunities; the report never leaves your browser.
About this tool
There is no server behind Page Size Checker. Page Size Checker parses an exported Lighthouse/PageSpeed report locally and pulls out page weight, per-type transfer sizes and compression savings.
Because it reads a report you export, Page Size Checker cannot fetch the page itself — browsers block cross-origin requests — so run Lighthouse or PageSpeed, save the JSON, and load it here. It behaves the same on desktop and mobile, with nothing stored remotely.
Frequently asked questions
What is Page Size Checker for?
Page Size Checker lets you check your input right in the browser, with the result shown instantly and nothing uploaded.
Do I need an account for Page Size Checker?
No — Page Size Checker needs no account, sign-up or installation.
Does Page Size Checker upload my data?
No — Page Size Checker processes everything locally in your browser, so nothing you enter is uploaded or stored.
How does Page Size Checker measure size and compression?
Page Size Checker reads the resource-summary, total-byte-weight and uses-text-compression audits from a Lighthouse or PageSpeed JSON report you paste, then shows transfer sizes and gzip/Brotli savings — all parsed locally.
Can I use Page Size Checker without a connection?
Yes — after the first load Page Size Checker runs entirely offline.