Lighthouse CI (LHCI) is Google's official tool for running Lighthouse audits in continuous integration pipelines. It catches performance regressions before they reach production.

What is Lighthouse CI?

Lighthouse CI is a suite of tools that integrate Lighthouse into your CI/CD workflow:

• @lhci/cli — Command-line tool for running audits (~2M monthly npm downloads)
• @lhci/server — Optional server for storing historical data
• GitHub App — Status checks on pull requests

Why Use Lighthouse CI?

83% of Fortune 500 companies have integrated automated performance testing into their CI/CD pipelines. Without it, regressions slip through:

1. Developer fixes performance issues
2. PR gets merged
3. Next week, someone adds a 500KB image
4. Performance tanks, nobody notices until users complain

LHCI solves this by running Lighthouse on every commit and failing builds that don't meet your standards.

Key Features

• Regression prevention — Fail builds when Core Web Vitals like LCP, CLS, and TBT (proxy for INP) drop
• Performance budgets — Set thresholds for scores and resource sizes
• Historical tracking — Compare builds over time
• Variance reduction — Run multiple times, use median results
• GitHub integration — Status checks and PR comments

Quick Start

Install and run:

npm install -g @lhci/cli
lhci autorun --collect.url=https://example.com --upload.target=temporary-public-storage

Or with a config file (lighthouserc.js):

module.exports = {
  ci: {
    collect: {
      url: ['https://example.com/'],
    },
    upload: {
      target: 'temporary-public-storage',
    },
  },
}

Then run:

lhci autorun

How It Works

The lhci autorun command executes three steps:

1. collect — Runs Lighthouse N times per URL
2. assert — Checks results against budgets/assertions
3. upload — Stores results (temporary storage, filesystem, or LHCI server)

Run lhci healthcheck --fatal separately to verify Chrome and config before autorun.

Results are saved to .lighthouseci/ locally.

What LHCI Measures

Lighthouse CI audits four categories on every run:

• Performance — Core Web Vitals (LCP, CLS, TBT as proxy for INP) and other speed metrics
• Accessibility — Screen reader support, color contrast, ARIA
• SEO — Meta tags, structured data, mobile-friendliness
• Best Practices — HTTPS, console errors, deprecated APIs

Each category gets a 0-100 score. Set thresholds in your config to block merges when scores drop.

Prerequisites

• Node.js 18+
• Chrome/Chromium installed
• A URL to test (can be localhost with startServerCommand)

Tutorials

Related

• Core Web Vitals Guide — Understand the metrics LHCI tracks
• Bulk Lighthouse Testing — Test entire sites with Unlighthouse
• LCP Guide | CLS Guide | INP Guide

Performance Impact

Why invest in performance testing? Research shows direct business impact:

• BBC loses 10% of users for every additional second of load time
• Amazon estimates every 100ms of latency costs 1% in sales
• Google research shows bounce probability increases 90% as load time goes from 1s to 5s

Resources

• GitHub Repository
• Official Documentation
• npm Package