> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/GoogleChrome/lighthouse/llms.txt
> Use this file to discover all available pages before exploring further.

# Lighthouse

> Automated auditing, performance metrics, and best practices for the web.

Lighthouse analyzes web pages and apps, collecting modern performance metrics and surfacing actionable insights on developer best practices. Run it from Chrome DevTools, the command line, or as a Node module — and get scores across Performance, Accessibility, SEO, and Best Practices.

<CardGroup cols={2}>
  <Card title="CLI Quickstart" icon="terminal" href="/quickstart-cli">
    Install Lighthouse and run your first audit in under a minute
  </Card>

  <Card title="Node.js Quickstart" icon="node-js" href="/quickstart-node">
    Use Lighthouse programmatically in your Node.js scripts
  </Card>

  <Card title="Configuration" icon="sliders" href="/configuration/overview">
    Customize audits, throttling, categories, and output formats
  </Card>

  <Card title="User Flows" icon="arrow-right-arrow-left" href="/running/user-flows">
    Audit multi-step interactions with navigation, timespan, and snapshot modes
  </Card>
</CardGroup>

## What Lighthouse measures

<CardGroup cols={2}>
  <Card title="Performance" icon="gauge-high">
    Core Web Vitals (LCP, CLS, INP), Time to Interactive, Speed Index, and more — all simulated on a mid-tier mobile device over 4G.
  </Card>

  <Card title="Accessibility" icon="universal-access">
    Automated checks powered by axe-core, covering ARIA usage, color contrast, keyboard navigation, and semantic markup.
  </Card>

  <Card title="SEO" icon="magnifying-glass">
    Crawlability, meta tags, structured data, mobile friendliness, and other ranking-relevant signals.
  </Card>

  <Card title="Best Practices" icon="shield-check">
    HTTPS, modern JavaScript APIs, secure headers, browser compatibility, and more.
  </Card>
</CardGroup>

## How to run Lighthouse

<Steps>
  <Step title="Choose your entry point">
    Lighthouse runs in three ways: directly inside **Chrome DevTools** (no install needed), via the **Node CLI** for automation, or as a **Node module** for programmatic integration.
  </Step>

  <Step title="Point it at a URL">
    Whether you use DevTools, the CLI (`lighthouse https://example.com`), or the Node API, Lighthouse launches Chrome, loads the page under controlled conditions, and collects data.
  </Step>

  <Step title="Read your report">
    Lighthouse generates an HTML report (or JSON/CSV) with scores, metric values, failing audits, and step-by-step guidance for every issue found.
  </Step>

  <Step title="Integrate and automate">
    Add Lighthouse to CI with [Lighthouse CI](https://github.com/GoogleChrome/lighthouse-ci), write custom audits for your own checks, or embed results in your toolchain.
  </Step>
</Steps>

## Explore the docs

<CardGroup cols={3}>
  <Card title="Running in DevTools" icon="chrome" href="/running/devtools">
    Zero-install auditing right in your browser
  </Card>

  <Card title="CLI reference" icon="rectangle-terminal" href="/api/cli-reference">
    Every flag and option for the command-line tool
  </Card>

  <Card title="Node API reference" icon="code" href="/api/node-api">
    Full API surface for programmatic use
  </Card>

  <Card title="Throttling" icon="signal" href="/configuration/throttling">
    How network and CPU throttling works
  </Card>

  <Card title="Plugins" icon="plug" href="/extend/plugins">
    Build and share custom audit categories
  </Card>

  <Card title="Understanding results" icon="chart-bar" href="/api/understanding-results">
    What the LHR object contains and how scores work
  </Card>
</CardGroup>