Lighthouse
Automated auditing for performance, accessibility, SEO, and best practices on web pages.
Pricing
Free / Open source
Type
Automation
Languages
JavaScript
// VERDICT
Reach for Lighthouse when you want repeatable lab audits of front-end performance and Core Web Vitals with concrete fix guidance, including in CI. Skip it when you need back-end load testing (k6/JMeter) or real-user field data.
Best for
Auditing front-end web performance (and accessibility, SEO, best practices) in a lab setting - Google's tool measures Core Web Vitals and gives actionable fixes, runnable from Chrome, CLI or CI.
Avoid when
You want back-end load testing, real-user (field) data, or multi-user concurrency rather than single-page audits.
CI/CD fit
Lighthouse CLI · Lighthouse CI · GitHub Actions · GitLab CI
Languages
JavaScript
Team fit
Frontend teams · Web performance engineers · Teams tracking Core Web Vitals
Setup
Maintenance
Learning
Licence
// BEST FOR
- Auditing front-end performance and Core Web Vitals (LCP, INP, CLS)
- Actionable suggestions for fixing performance issues
- Covering accessibility, SEO and best-practices in one run
- Repeatable lab measurements from Chrome, CLI or CI
- Enforcing performance budgets via Lighthouse CI
- A free, Google-maintained standard for web vitals
// AVOID WHEN
- You need back-end load testing (k6/JMeter/Gatling)
- You want real-user (field) data, not lab measurements
- You need many concurrent simulated users
- You're testing APIs rather than rendered pages
- Single-page audits don't reflect your performance risk
- You want server-side throughput/latency under load
// QUICK START
npm install -g lighthouse
lighthouse https://example.com --output html --view
# or use Lighthouse CI (lhci autorun) to enforce budgets in the pipeline// ALTERNATIVES TO CONSIDER
| Tool | Choose it when |
|---|---|
| WebPageTest | You want real-browser waterfalls and multi-location front-end testing. |
| Playwright | You want to capture performance metrics within scripted E2E flows. |
// FEATURES
- Performance, Accessibility, SEO, Best Practices, and PWA audits
- Core Web Vitals measurement (LCP, INP, CLS)
- Available in Chrome DevTools, CLI, and Node API
- Lighthouse CI for budgets and regression checks
- JSON and HTML reports
- Plugin system for custom audits
// PROS
- Default standard for web performance audits
- Excellent CI integration via Lighthouse CI
- Backed by the Chrome team
- Covers a11y and SEO alongside performance
// CONS
- Lab-only — synthetic, not real-user data
- Score variance between runs requires multiple samples
- Chrome-based metrics may not match other engines
// EXAMPLE QA WORKFLOW
Run Lighthouse from Chrome, the CLI, or Lighthouse CI
Audit the target page for performance and Core Web Vitals
Review the actionable suggestions
Set performance budgets
Enforce budgets in CI via Lighthouse CI
Pair lab results with real-user monitoring for the field view
// RELATED QA.CODES RESOURCES
Cheat sheets
Glossary
// RELATED TOOLS
Similar tools in Performance
- API TestingKarate
BDD-style API, performance, and UI testing in a single framework.
- PerformanceApache JMeter
Java-based load testing tool for performance and stress testing.
- Performancek6
Modern load testing tool with developer-friendly JavaScript scripting.
- PerformanceGatling
Scala-based load testing tool with detailed performance reports.
// Practise with Lighthouse
Put Lighthouse to work on a realistic app with seeded bugs, scenarios and automation tasks.