# micmro/performance-bookmarklet

Performance-Bookmarklet helps to analyze the current page through the Resource Timing API, Navigation Timing API and User-Timing - requests by type, domain, load times, marks and more. Sort of a light live WebPageTest.

Repository: https://github.com/micmro/performance-bookmarklet
Canonical: https://ross.abutalabs.com/products/performance-bookmarklet
Language: JavaScript
License: MIT
License Family: permissive
Topics: webperf, bookmarklet, navigation-timing, resource-timing, analyzer, performance, waterfall, requests, performance-metrics, user-timing, browser-extension
Last push: 2023-03-03T11:28:45+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 4350, "days_push": 1279, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1154, forks 84 (observed 2026-08-28T04:03:47.685100+00:00)

## What it is
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
- artifact type: plugin
- maturity: maintenance
- function: monitoring, analytics, developer-tools
- domain: web-development, performance, browser-extensions, developer-tools
- platform: browser, browser-extension
- tags: bookmarklet, webperf, waterfall, resource-timing, navigation-timing, user-timing, page-speed, browser-extension

## Member repositories
- micmro/performance-bookmarklet (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:47.685100+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T08:39:28.969287+00:00, confidence not recorded.
  - readme: https://github.com/micmro/performance-bookmarklet (fetched 2026-08-28T04:03:47.685100+00:00, sha 1e065ac900a7)
- Data as of 2026-08-30T08:39:29.467469+00:00.