lighthouse

What is lighthouse?

Lighthouse is an open-source, automated tool for improving the quality of web pages. It can be run against any web page, public or requiring authentication. It has audits for performance, accessibility, progressive web apps, SEO, and more.

What are lighthouse's main functionalities?

Performance Audits

This feature allows you to run performance audits on a web page. The code sample demonstrates how to launch a headless Chrome instance, run Lighthouse against a URL, and log the performance score.

const lighthouse = require('lighthouse');
const chromeLauncher = require('chrome-launcher');

(async () => {
  const chrome = await chromeLauncher.launch({chromeFlags: ['--headless']});
  const options = {logLevel: 'info', output: 'json', onlyCategories: ['performance'], port: chrome.port};
  const runnerResult = await lighthouse('https://example.com', options);
  console.log('Report is done for', runnerResult.lhr.finalUrl);
  console.log('Performance score was', runnerResult.lhr.categories.performance.score * 100);
  await chrome.kill();
})();

Accessibility Audits

This feature allows you to run accessibility audits on a web page. The code sample demonstrates how to launch a headless Chrome instance, run Lighthouse against a URL, and log the accessibility score.

const lighthouse = require('lighthouse');
const chromeLauncher = require('chrome-launcher');

(async () => {
  const chrome = await chromeLauncher.launch({chromeFlags: ['--headless']});
  const options = {logLevel: 'info', output: 'json', onlyCategories: ['accessibility'], port: chrome.port};
  const runnerResult = await lighthouse('https://example.com', options);
  console.log('Report is done for', runnerResult.lhr.finalUrl);
  console.log('Accessibility score was', runnerResult.lhr.categories.accessibility.score * 100);
  await chrome.kill();
})();

SEO Audits

This feature allows you to run SEO audits on a web page. The code sample demonstrates how to launch a headless Chrome instance, run Lighthouse against a URL, and log the SEO score.

const lighthouse = require('lighthouse');
const chromeLauncher = require('chrome-launcher');

(async () => {
  const chrome = await chromeLauncher.launch({chromeFlags: ['--headless']});
  const options = {logLevel: 'info', output: 'json', onlyCategories: ['seo'], port: chrome.port};
  const runnerResult = await lighthouse('https://example.com', options);
  console.log('Report is done for', runnerResult.lhr.finalUrl);
  console.log('SEO score was', runnerResult.lhr.categories.seo.score * 100);
  await chrome.kill();
})();

Progressive Web App (PWA) Audits

This feature allows you to run Progressive Web App (PWA) audits on a web page. The code sample demonstrates how to launch a headless Chrome instance, run Lighthouse against a URL, and log the PWA score.

const lighthouse = require('lighthouse');
const chromeLauncher = require('chrome-launcher');

(async () => {
  const chrome = await chromeLauncher.launch({chromeFlags: ['--headless']});
  const options = {logLevel: 'info', output: 'json', onlyCategories: ['pwa'], port: chrome.port};
  const runnerResult = await lighthouse('https://example.com', options);
  console.log('Report is done for', runnerResult.lhr.finalUrl);
  console.log('PWA score was', runnerResult.lhr.categories.pwa.score * 100);
  await chrome.kill();
})();

Other packages similar to lighthouse

web-vitals

Web Vitals is a library for measuring essential metrics that are critical to delivering a great user experience on the web. It focuses on metrics like Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS). Unlike Lighthouse, which provides a comprehensive audit, Web Vitals focuses specifically on user-centric performance metrics.

axe-core

Axe-core is a JavaScript library that helps developers find and fix accessibility issues in their web applications. It is highly focused on accessibility audits, whereas Lighthouse provides a broader range of audits including performance, SEO, and PWA.

psi

PSI (PageSpeed Insights) is a tool that provides insights into how well a page performs on both mobile and desktop devices. It uses Lighthouse under the hood but is more focused on providing actionable insights for performance improvements. PSI is more user-friendly and less customizable compared to running Lighthouse directly.

README

Lighthouse

Feature switching server using lightswitch and upnode

Changelog

10.0.1 (2023-02-14)

Full Changelog

We expect this release to ship in the DevTools of Chrome 112, and to PageSpeed Insights within 2 weeks.

Core

• reduce DevTools flakiness (#14782)
• doctype: only consider main frame (#14795)
• paste-preventing-inputs: rephrase description (#14794)

Deps

• move quibble to dev deps (#14780)

Docs

• split changelog at 10.0 (#14778)
• changelog: minor v10 edits (#14777)

Misc

• update .npmignore (#14779)

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