micmro/performance-bookmarklet

Health v2 · maintenance only

Adoption not part of the score

1154 stars · 84 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

A bookmarklet and browser extension (Chrome/Firefox) that analyzes the current page's performance using the Resource Timing, Navigation Timing, and User Timing APIs. It visualizes request waterfalls, load times, and resource breakdowns by type and domain, acting as a lightweight live WebPageTest.

Use cases

• analyze page load performance in the browser
• view a waterfall of network requests for the current page
• see requests grouped by type and domain
• inspect navigation timing metrics on any site
• check performance.mark and performance.measure user timings
• debug slow-loading resources without external tools

When to choose

• you need a quick, zero-install page performance analysis in the browser
• you want a lightweight alternative to WebPageTest for live pages
• you prefer a bookmarklet or extension over CLI tools like Lighthouse
• you need to inspect Resource Timing and User Timing data visually

When to avoid

• you need scripted or CI-automated performance audits
• you require deep lab testing, throttling, or filmstrip screenshots
• the site's Content Security Policy blocks bookmarklet injection and you can't use the extension

Facets

plugin · maturity maintenance

monitoring analytics developer-tools web-development performance browser-extensions developer-tools browser browser-extension bookmarklet webperf waterfall resource-timing navigation-timing user-timing page-speed browser-extension

Member repositories

For agents

markdown · JSON · MCP: product_card(name="micmro/performance-bookmarklet")