Missed the action at this year's Chrome Dev Summit? Catch up with our playlist on YouTube. Watch now.

Lighthouse 2.5 Updates

Lighthouse 2.5 is now released! Highlights include:

See the release notes for the full list of new features, changes, and bug fixes coming to Lighthouse in version 2.5.

chrome-launcher is now a standalone Node module

chrome-launcher is now a standalone Node module, making it easier to launch Google Chrome from your own Node applications.

Five new audits

Appropriate aspect ratios

Category: Best Practices

The Does not use images with appropriate aspect ratios audit alerts you when an image's rendered aspect ratio is significantly different than the image's actual dimensions. The aspect ratio is the ratio between width and height. If the ratio is significantly different when rendered, then the image probably looks distorted.

The \ Figure 1. The Does not use images with appropriate aspect ratios audit

JavaScript libraries with security vulnerabilities

Category: Best Practices

The Includes front-end JavaScript libraries with known security vulnerabilities audit warns you about how many vulnerabilities a library has, as well as the highest severity level among those vulnerabilities.

The \ Figure 2. The Includes front-end JavaScript libraries with known security vulnerabilities audit

Unused JavaScript

Category: Performance

The Unused JavaScript audit breaks down how much JavaScript a page loads but does not use during startup.

The \ Figure 3. The Unused JavaScript audit

Low server response times

Category: Performance

The Keep server response times low (TTFB) audit measures how long it takes the client to receive the first byte of the main document. If Time To First Byte (TTFB) is long, then the request is taking a long time traveling through the network, or the server is slow.

The \ Figure 4. The Keep server response times low audit

Console errors

Category: Best Practices

The Browser errors were logged to the console audit alerts you to any errors that are logged to the console as the page loads.

The \ Figure 5. The Browser errors were logged to the console audit

Throttling guide

Check out the new Throttling Guide to learn how to conduct high-quality, packet-level throttling. This guide is intended for advanced audiences.