The Beginner’s Guide to Chrome Developer Tools

Chrome Developer Tools is a comprehensive toolkit for developers, built directly into the Chrome browser. These tools let you edit web pages in real time, diagnose problems more quickly, and build better websites faster.

Even if you’re not a developer, though, you can still get some use out of Developer Tools.

What are Chrome Developer Tools?

Here’s what you’ll see when you open Developer Tools:

A standard web page, but with a new set of tools open in a panel on the right of the page.

There are three tabs at the top of the Developer Tools window, and a further six that you can see by clicking the >> symbol next to them.

The tabs are:

• Elements
• Console
• Source
• Network
• Application
• Security
• Memory
• Performance
• Audits

They don’t always stay in this order—Chrome moves them around based on which you opened last.

By default, Developer Tools opens with the Elements tab open.

Elements shows you the HTML used to build the page you’re looking at, together with any inline CSS.

Console deals with JavaScript. It gives you information about interactive elements on a page. In Console, you can write JavaScript to interact with the web page you’re viewing, and it also lets you write messages to yourself in the JavaScript of websites you’re building, which then show up in Console to show that the JS was executed.

The Sources tab shows you where all the files that were used to make the website are stored and lets you inspect them.

The Network tab shows you all the files that are loading in the URL you’re looking at.

You get a waterfall and deep data on all the items loaded, including initiator and time to load that element.

Application shows you what’s in your browser storage: in-browser databases like Web SQL, local storage, and more. It also gives you granular control over your cookies.

Security gives you basic security information, letting you view a site’s HTTPS certificate and TLS status.

Finally, there’s Audits, which autogenerates reports on site functionality and structure to help developers improve performance.

Developer Tools is updated with each new Chrome release. To make sure they’re up-to-date, go to Components by typing chrome://components into your omnibar, select “Recovery” and check for updates.

Important: You can’t change the code on the website with Developer Tools. You’d need access to the site’s backend for that. Only the code your browser uses to display the website is changed. So even if you’re a total beginner, you can do anything you like with Developer Tools with no real risk. Close the window, go back to the website, and everything is the same as it was before.

Let’s start using Developer Tools.

How to open Chrome Developer Tools

You can open Developer Tools with keyboard shortcuts or through the Chrome menu.

The keyboard shortcuts are:

• Mac OS: CMD+Shift+J or CMD+Shift+C
• Linux, Chromebook and Windows: Ctrl+Shift+J

From the Chrome menu:

Open the Chrome menu and go to “More Tools” > “Developer Tools.”

Finally, you can right-click (Windows) or Ctrl-click (Mac) anything on a web page and select “Inspect Element” to open Developer Tools.

The Developer Tools panel will open in whatever web page you’re on. You need to open them again for each new Chrome window, but you can navigate between web pages with them open.

What about on mobile?

Opening Developer Tools on mobile

You can’t access Developer Tools directly on Android. Instead you’ll need to use Remote Debugging. The basic process works like this:

1. Connect your Android device
2. Open Developer Tools and go to “More Tools” > “Remote Devices”
3. Authorize the remote access on your Android device

There doesn’t seem to be a way to do this at all on iOS devices.

5 common uses of Chrome Developer Tools for beginners

Just because you’re not a developer doesn’t mean Developer Tools aren’t for you. Here are five ways you can make your life easier with Developer Tools.

Most of these will use the Elements tab. Here’s a quick guide to that:

The top section shows the HTML for the site.

The bottom left section shows the CSS styles applied to that page.

The bottom right shows the CSS layout visually so you know what you’re looking at.

1. Inspect page tags

One of the most important elements of onpage SEO is simple h1 and h2 tags. Snoop under the hood and you’ll find a lot of folks (including those who should know better) aren’t getting this stuff right.

Once you’ve seen pages where the h1 was an unoptimized image, or pages with four h1 tags, you begin to appreciate the urgency of the situation. And tools like Screaming Frog are great but they’re not always 100% accurate. It’s best to check by hand. It’s also very easy.

Open a page, then open Developer Tools. In the Elements tab, press CMD+F or Ctrl-F to search and search “h1” to see your page’s tag(s):

2. Edit CSS

Developer Tools lets you change the CSS of a page directly in your browser. You can trial color combinations, fonts—anything that’s governed by CSS. You don’t have to mess around with the stylesheet and you often don’t have to write a single character of code.

Suppose I want to see what the FYI homepage would look like with red text.

I open the page, then open Developer Tools. Ctrl-click or right-click the element you want to change on the web page. In the Elements tab I find the color for the element in the bottom left panel:

Click on the color box and I can simply click on another color in Chrome Color Picker (more on this later). The text changes immediately.

Probably going to leave that black.

3. See what they built the website with

When you visit a website, it’s not always easy to see what CMS was used to build it. But you can find out easily with Developer Tools.

Open the site and Developer Tools, then look at the top right of the Styles panel in the Elements tab:

Right-click or Ctrl-click on the link that starts “style.css” and select “Copy link address.” Paste the link into a new tab and it will tell you the CDN and theme used to build the site—in this case, it’s built using Divi on WordPress.

4. Write into the website

If you’re working up copy for a new web page, you can go to one that already exists and write directly into it with Developer Tools. So if layout or sizing is an issue, you can check your copy still looks good in the environment it’s going to be displayed.

Here’s how.

Open Developer Tools on a web page—you can do this with any web page.

With the Elements tab open, right-click a piece of text on the page. You’ll see the relevant HTML highlighted:

Find the three vertical dots on the left side of the HTML for that element, click them, and select “Edit as HTML.”

Even if you don’t know HTML from the DMV, you can still do this: all you’re looking for is the text you clicked on, inside all the code. The HTML is all color-coded, while the text is black. Click on it, and you can type in whatever you like:

Click on the background to exit the HTML and your changes appear in the page itself:

Yes, it looked better before. But this way you can find out for sure, and tailor your copy precisely to the layout and design it will be used with.

5. See it on mobile

…and on any other viewport you want. Developer Tools lets you manage viewport appearance using both preselected sizes and free scaling.

Open Developer Tools and look at the top menu bar, where Elements, Console, and Source are displayed. You’ll see two icons on the far left of that bar; the one that looks like a stack of mobile devices is what we’re after.

Click that and you’ll see the site you’re on displayed as if you were a mobile visitor:

That’s cool, but there’s more you can do with these controls. The icon lets you toggle between mobile and desktop versions of the site. And the controls at the top of the screen let you adjust viewport size. Here’s how it looks on a mobile with a big screen:

Here’s how it looks on a tablet:

Use these controls to choose the viewport size you want:

Use this dropdown to see what the site looks like on different devices:

Set viewport size yourself:

And even mimic different connection qualities as you navigate the site:

You can do all that and more from the menu bar at the top.

What about if you want to stretch the uses for Developer Tools a little more?