Chrome DevTools - 20+ Tips and Tricks

Tips and tricks

Below are just a few of the hundreds of things you can do with Chrome DevTools. It also makes for a good crash course on the tools if you haven't used them before.

Quick file switching

You can easily access any file within a current project or web page by pressing Cmd + P (Ctrl + P) when Chrome DevTools is open and searching for the name.

Pretty print

Did you know Chrome DevTools has a pretty print featured built in? You can easily change the formatting of your minimized code by clicking on {}.

Edit HTML element

You can edit HTML on the fly and preview the changes by selecting any element, choosing a DOM element within the panel, and double clicking on the opening tag to edit it. The closing tags are automatically updated for you. Any changes will show up in your browser as if the change had actually been made to the source code.

Edit CSS property

Just like with editing HTML, you can also change CSS in Chrome DevTools and preview what the result will look like. This is probably one of the most common uses for this tool. Simply select the element you want to edit and under the styles panel you can add/change any CSS property you want.

Search source code

You can quickly search all of your source code by pressing Cmd + Opt + F (Ctrl + Shift + F).

JavaScript breakpoints

When debugging JavaScript it is sometimes useful to set breakpoints. You can set breakpoints in Chrome DevTools by clicking on the line number you want to break at then press Cmd + R (Ctrl + R) to refresh the page. The page will then run right to that breakpoint.

Go to line number

You can automatically skip to a line in your code by pressing Cmd + O (Ctrl + O) and using the line syntax. In the example below we entered :375:18 to go to line 375, column 18.

Multiple cursors

Ever have multiple lines you need to add something to? You can easily add multiple cursors by pressing Cmd + Click (Ctrl + Click) and entering information on multiple lines at the same time.

Dock position

You can also change the Chrome DevTools dock position. You can either undock into a separate window, or dock it on the left, bottom, or right side of the browser. The dock position can be changed by pressing Cmd + Shift + D (Ctrl + Shift + D) or through the menu.

Clear cookies

You can also easily clear cookies from the Chrome DevTools. This can be especially useful when testing and debugging third party plugins. In the Application panel go to Storage > Cookies to either clear all cookies or an individual cookie.

Device mode

You can test your website and media queries to see if your responsive design is breaking anywhere by going into device mode. Or perhaps you need to see at what resolution the page is breaking at so you know where to apply a media query.

To enter device mode click on the small phone and tablet icon in Chrome DevTools or press Cmd + Shift + M (Ctrl + Shift + M). You can then choose what device and resolution to emulate, add a network throttle, and even define the device orientation.

Color palette and picker

The custom color palette will pull from the website style sheet. You can access them by simply clicking on the color block in the style panel. There is also a color picker that can be used to pick out colors from a web page directly.

Change color format

You can toggle between RGBA, HSL, and hexadecimal formatting by pressing Shift + Click on the color block.

Toggle element state

Have you ever tried to figure out where a hidden style is coming from, say the :hover selector? In Firefox Developer Tools you can see this when selecting the element, but not in Chrome DevTools. However, there is something better, called Toggle Element State. This allows you to force an element state, like :hover, so that you can then use the styles panel to see the properties.

Copy image as data URI (base64 encoded)

You can save any image from a webpage out as a data URI or rather base64 encoded. There is no need to use a free online converter as it is already built into Chrome DevTools. In the Network panel click on an image and then right click on it to have the option to Copy image as data URI.

You will get the image in the following format:

data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAMAAAADACAIAAADdvvtQAAAgNklEQVR42u2dd5gVZZbG/WNn1dmdWXdmNu88O7uz7uzO7jozKiqCSFJERUQFBARBRAREcm5yzlmBBprcQJNBck6SY5MbJOfO+XY3d39wd3qaqltfV9X9qm71vd/31OMfcu/tCm+d75z3vOecJ...

Network filmstrip

The network filmstrip feature allows you to see how your page renders from start to finish by grabbing screenshots throughout the loading process. This can be a great way to see how your font is rendering and if you're dealing with issues such as FOIT or FOUT.

In the Network panel click on the settings icon, check the Capture screenshots option, and then press Cmd + R (Ctrl + R) to refresh the page. After the page has refreshed it will show you how your page rendered from start to finish.

Monitor performance

The performance feature allows you to easily see what is costing you the most time and resources. The performance details can be broken down in many different ways, such as the time, activity, and source.

In the Performance panel press Cmd + E (Ctrl + E) and then Ctrl + R (Cmd + R) to refresh the page. Record the amount of time that you want to be monitored. You can then click Stop and evaluate the results.

DOMContentLoaded

We have a great article on blocking the DOM and how to fix it. This feature allows you to see the exact DOMContentLoaded time and total load time. Checking these values can be beneficial in improving the overall performance of your website or application.

In the Network panel click on the settings icon, check the Show overview option, and then press Cmd + R (Ctrl + R) to refresh the page. A blue line will show up for DOMContentLoaded and a red line for total load time. Normally everything that is left of or touching the blue line are assets that are blocking the DOM, or also referred to as render blocking resources.

Network throttling profiles

You can now also add custom networking throttling profiles. This can be beneficial if you are wanting to test more accurately at a specific speed.

In the Network panel click the Throttle drop down and then Add.... In the Network Throttling Profiles click Add custom profile... and add the profile with your specifications.

Security check

The Security panel can be very useful to check if the SSL/TLS certificate is valid, whether or not the connection is secure, and if all resources are served securely. This is great for for debugging HTTPS migrations and quickly fixing mixed content warnings.

In the Security panel press Cmd + R (Ctrl + R) to refresh the page. It will then display the relevant security information.

Validating Google AMP HTML

Google AMP is an open source initiative to speed up the web using lightweight HTML pages. For Google to index the AMP version of your page you must make sure it is validated.

In the Console panel append #development=1 to the AMP version in your browser's address bar and then press Cmd + R (Ctrl + R) to refresh the page. It will display if it successfully validated below. Read more about AMP validation errors.

Summary

As you can see Chrome DevTools has numerous features to help you develop better, debug faster, and measure more efficiently the performance of your website or application. The tips mentioned above are just a few of the many features available. Do you have a favorite DevTools feature that we missed? If so, let us know in the comments below.

• Read more in-depth about Chrome DevTools on the official Google Developers page.
• Subscribe for Chrome DevTools updates on their web update page.