README

performance-leaderboard

A plugin to run Lighthouse against a set of urls to see which site is the fastest.

Installation

npm install performance-leaderboard

Features

Median Run Selection: performance-leaderboard will run Lighthouse on the same site multiple times and select the Median run. It factors in First Contentful Paint, Largest Contentful Paint, and Time to Interactive when selecting the median run.

Usage

Create a test file, say sample.js:

const PerfLeaderboard = require("performance-leaderboard");

(async function() {

    let urls = [
        "https://www.gatsbyjs.org/",
        "https://nextjs.org/",
        "https://www.11ty.dev/",
        "https://vuejs.org/",
        "https://reactjs.org/",
        "https://jekyllrb.com/",
        "https://nuxtjs.org/",
        "https://gohugo.io/",
    ];

    // Create the options object (not required)
    const options = {
        axePuppeteerTimeout: 30000, // 30 seconds
        writeLogs: true, // Store audit data
        logDirectory: '.log', // Default audit data files stored at `.log`
        readFromLogDirectory: false, // Skip tests with existing logs
        // onlyCategories: ["performance", "accessibility"],
        chromeFlags: ['--headless'],
        freshChrome: "site", // or "run"
        launchOptions: {}, // Puppeteer launch options
    }

    // Run each site 3 times with default options
    console.log( await PerfLeaderboard(urls) );

    // Or run each site 5 times with default options
    console.log( await PerfLeaderboard(urls, 5) );

    // Or run each site 5 times with custom options
    console.log( await PerfLeaderboard(urls, 5, options) );
})();

Run node sample.js.

Sample Output

[
    {
        url: 'https://www.11ty.dev/',
        requestedUrl: 'https://www.11ty.dev/',
        timestamp: 1623525988492,
        ranks: { hundos: 1, performance: 1, accessibility: 1, cumulative: 1 },
        lighthouse: {
            version: '8.0.0',
            performance: 1,
            accessibility: 1,
            bestPractices: 1,
            seo: 1,
            total: 400
        },
        firstContentfulPaint: 1152.3029999999999,
        firstMeaningfulPaint: 1152.3029999999999,
        speedIndex: 1152.3029999999999,
        largestContentfulPaint: 1152.3029999999999,
        totalBlockingTime: 36,
        cumulativeLayoutShift: 0.02153049045138889,
        timeToInteractive: 1238.3029999999999,
        maxPotentialFirstInputDelay: 97,
        timeToFirstByte: 54.63900000000001,
        weight: {
            summary: '14 requests • 178 KiB',
            total: 182145,
            image: 124327,
            imageCount: 10,
            script: 7824,
            scriptCount: 1,
            document: 30431,
            font: 15649,
            fontCount: 1,
            stylesheet: 3914,
            stylesheetCount: 1,
            thirdParty: 15649,
            thirdPartyCount: 1
        },
        run: { number: 2, total: 3 },
        axe: { passes: 850, violations: 0 },
    }
]

Rankings

In the return object you’ll see a ranks object listing how this site compares to the other sites in the set. There are a bunch of different scoring algorithms you can choose from:

ranks.performance
- The highest Lighthouse performance score.
- Tiebreaker given to the lower SpeedIndex score.
ranks.accessibility
- The highest Lighthouse accessibility score.
- Tiebreaker given to lower Axe violations.
- Second tiebreaker given to highest Axe passes (warning: each instance of an Axe rule passing is treated separately so this will weigh heavily in favor of larger pages)
ranks.hundos
- The sum of all four Lighthouse scores.
- Tiebreaker given to the lower Speed Index / Total Page Weight ratio.
ranks.cumulative (the same as hundos but with an Axe tiebreaker)
- The sum of all four Lighthouse scores.
- Tiebreaker given to the lower Axe violations.
- Second tiebreaker given to the lower Speed Index / Total Page Weight ratio.

Changelog

v4.0.0 Major version upgrade of lighthouse dependency from v6.5 to v7.2
v4.1.0 Update lighthouse to v7.3
v5.0.0 Update lighthouse to v8.0
v5.1.0 Adds axePuppeteerTimeout option. Adds carbonAudit option.
v5.2.0 Update lighthouse from v8.0 to v8.2
v5.3.0 Update lighthouse from v8.2 to v8.5
v9.0.0 Update lighthouse to v9.0. Removes carbonAudit, upstream API was removed.
v9.2.0 Update lighthouse to v9.2.

Usage no npm install needed!