CrUX Benchmark Builder

Comparative Core Web Vitals reporting from the Chrome UX Report History API

1. Connect

Your API key never reaches this tool's server, ever.
  • Used only to call Google's Chrome UX Report API directly from your browser.
  • Remembered locally in this browser only (via localStorage) so you don't have to retype it each visit — it isn't synced, shared across browsers/devices, or visible to anyone else using this tool.
  • Google's own CrUX API docs note these keys are safe to embed in URLs — they're free-tier, rate-limited, and can't touch billing or other Cloud resources, a different risk class than a typical secret credential.
  • Using "Save to server & get link" only sends the finished report and the list of domains you compared — your key is never part of that request.
  • Use "Forget key" below any time to remove it from this browser.

Don't have one? Enable the "Chrome UX Report API" in a Google Cloud project, then create an API key under Credentials — see Google's CrUX API documentation for the full walkthrough.

2. Choose sites

One per line: Display Name, domain.com. Paste a full URL and only the domain is used — this compares whole-origin traffic, not individual pages. Up to 20 domains per run.