lighthouse

Lighthouse Lighthouse analyzes web apps and web pages, collecting modern performance metrics and insights on developer best practices. Using Lighthouse Using Lighthouse in Chrome DevTools Using the Chrome extension Using the Node CLI CLI options Using the Node module Viewing a report Online Viewer Docs & Recipes Developing Lighthouse Setup Run Tests Docs Associated Products and Projects Lighthouse Integrations in Web Perf services Lighthouse Integrations in non-Web Perf services Plugins Related projects FAQ How does Lighthouse work? Can I configure the lighthouse run? How does Lighthouse use network throttling, and how can I make it better? Are results sent to a remote server? How do I get localized Lighthouse results? How do I author custom audits to extend Lighthouse? How do I contribute? Using Lighthouse in Chrome DevTools Lighthouse is integrated directly into the Chrome DevTools, under the "Lighthouse" panel. Installation: install Chrome. Run it: open Chrome DevTools, select the Lighthouse panel, and hit "Generate report". Using the Chrome extension The Chrome extension was available prior to Lighthouse being available in Chrome Developer Tools, and offers similar functionality. Installation: install the extension from the Chrome Web Store. Run it: follow the extension quick-start guide. Using the Node CLI The Node CLI provides the most flexibility in how Lighthouse runs can be configured and reported. Users who want more advanced usage, or want to run Lighthouse in an automated fashion should use the Node CLI. NoteLighthouse requires Node 22 (LTS) or later. Installation: npm install -g lighthouse # or use yarn: # yarn global add lighthouse Run it: lighthouse https://airhorner.com/ By default, Lighthouse writes the report to an HTML file. You can control the output format by passing flags. CLI options $ lighthouse --help lighthouse <url> <options> Logging: --verbose Displays verbose logging [boolean] [default: false] --quiet Displays no progress, debug logs, or errors [boolean] [default: false] Configuration: --save-assets Save the trace contents & devtools logs to disk [boolean] [default: false] --list-all-audits Prints a list of all available audits and exits [boolean] [default: false] --list-trace-categories Prints a list of all required trace categories and exits [boolean] [default: false] --additional-trace-categories Additional categories to capture with the trace (comma-delimited). [string] --config-path The path to the config JSON. An example config file: core/config/lr-desktop-config.js [string] --preset Use a built-in configuration. WARNING: If the --config-path flag is provided, this preset will be ignored. [string] [choices: "perf", "experimental", "desktop"] --chrome-flags Custom flags to pass to Chrome (space-delimited). For a full list of flags, see https://bit.ly/chrome-flags Additionally, use the CHROME_PATH environment variable to use a specific Chrome binary. Requires Chromium version 66.0 or later. If omitted, any detected Chrome Canary or Chrome stable will be used. [string] [default: ""] --port The port to use for the debugging protocol. Use 0 for a random port [number] [default: 0] --hostname The hostname to use for the debugging protocol. [string] [default: "localhost"] --form-factor Determines how performance metrics are scored and if mobile-only audits are skipped. For desktop, use --preset=desktop instead. [string] [choices: "mobile", "desktop"] --screenEmulation Sets screen emulation parameters. See also --preset. Use --screenEmulation.disabled to disable. Otherwise set these 4 parameters individually: --screenEmulation.mobile --screenEmulation.width=360 --screenEmulation.height=640 --screenEmulation.deviceScaleFactor=2 --emulatedUserAgent Sets useragent emulation [string] --max-wait-for-load The timeout (in milliseconds) to wait before the page is considered done loading and the run should continue. WARNING: Very high values can lead to large traces and instability [number] --enable-error-reporting Enables error reporting, overriding any saved preference. --no-enable-error-reporting will do the opposite. More: https://github.com/GoogleChrome/lighthouse/blob/main/docs/error-reporting.md [boolean] --gather-mode, -G Collect artifacts from a connected browser and save to disk. (Artifacts folder path may optionally be provided). If audit-mode is not also enabled, the run will quit early. --audit-mode, -A Process saved artifacts from disk. (Artifacts folder path may be provided, otherwise defaults to ./latest-run/) --only-audits Only run the specified audits [array] --only-categories Only run the specified categories. Available categories: accessibility, best-practices, performance, seo [array] --skip-audits Run everything except these audits [array] --disable-full-page-screenshot Disables collection of the full page screenshot, which can be quite large [boolean] --ignore-status-code Disables failing on all error status codes, and instead issues a warning. [boolean] --url-file The path to a file containing newline-delimited URLs to audit. [string] --fail-fast Stop auditing remaining URLs immediately if a run fails. [boolean] Output: --output Reporter for the results, supports multiple values. choices: "json", "html", "csv" [array] [default: ["html"]] --output-path The file or directory path to output the results. Use 'stdout' to write to stdout. Directories in the path must already exist. If a directory is spec