PerfDebugger - Frontend Performance

About

PerfDebugger shows Core Web Vitals as you browse — instantly. No 60-second Lighthouse audits. No simulated devices. Just real metrics from your real browser, updated live every second.

Built for frontend developers who debug performance daily.

WHAT YOU GET
• Real-time Core Web Vitals: LCP, FCP, CLS, INP, TTFB
• Live memory monitoring with JS heap tracking and leak detection
• Automatic slow-resource detection (flags requests over 1 second)
• Framework-agnostic — works on any website
• 100% local, no tracking, no servers

WHY NOT LIGHTHOUSE?
Lighthouse is great for formal audits and CI pipelines — but it takes 30-60 seconds per run, uses simulated throttling, and clears the cache on every run. PerfDebugger is the opposite: instant results, real device data, always visible. Different tools for different jobs.

PRIVACY FIRST
All metrics are stored locally in your browser with chrome.storage.local. Nothing leaves your machine. No analytics, no tracking, no accounts. Old data (>7 days) is auto-cleaned.

PERMISSIONS
• storage — save metrics locally
• activeTab — read performance data from the current tab
• alarms — schedule cleanup of old data
• <all_urls> — measure performance on any website you visit

Free. Open source. No sign-up required.