PRO 30% Free • Stripe ($15) & Razorpay (₹899)

The Box Model in DevTools

Top Course Staff · 3 min read · Developer tools · PRO · 30% Free Preview Available

The Box Model in DevTools

Introduction

All HTML elements are boxes made up of four components: a content container, padding, border, and margin. In ourBox Model lessonwe introduce these four properties and use them to position elements on a website. If you have not taken this lesson, we recommend you do so now, before continuing.

In this article, we will introduce how Google Chrome’s DevTools can be used to view the box around each element on a web page.

You can use Google Chrome’s DevTools to view the box around every element on a web page. There are a few different ways to open DevTools, depending on your platform:

Mac

  • command+option+ i
  • View > Developer > Developer Tools
  • Chrome 3 dot menu ⋮ > More Tools > Developer Tools

Windows

  • control+shift+ i
  • F12
  • Chrome 3 dot menu ⋮ > More Tools > Developer Tools

Use whichever method works best for you. When you have the DevTools open, navigate to theElementstab.

Elements Tab

Elements Tab

In this tab you can view all of the elements on the current page. From this view, you can select the element of interest, which will open a new column on the right side of DevTools. Select the tab labeledComputedon the top of the rightmost column.

Computed Tab

Computed Tab

The selected element’s box should appear at the top of the pane. Hovering over each property of the box will cause the property to be highlighted in the web page.

If you know the element you want to inspect, going through all of the steps listed above is unnecessary. Instead, you can right click the element you want to observe and select the Inspect button. This will display DevTools on the right side of the browser with the element selected in the Elements tab. To view the element’s box, you can select the Computed tab.

If you’d like some more info or a refresher on how to use Google Dev Tools, take a look atthis video.

Exercise I: View a Website’s Box Model Dimensions

Complete the following steps within the current web browser view.

  • In a new tab navigate to the CodecademyWikipediapage.
  • Right click (orCtrland click simultaneously) the Contents navigation box displayed in the image below:
  • SelectInspect.
  • Select the Computed tab at the top of the rightmost column.
  • Hover over the different properties of the logo’s box. The corresponding space on the web page should be highlighted when you do this.
Dropdown image

Dropdown image

Now that you know how to view the box of an element we’ll modify the box’s values with DevTools.

To modify the values of the box double click the property value, assign it a new number, and press enter. You can also adjust the value incrementally by double clicking the value and using the up or down arrow keys.

Selecting Values

Selecting Values

In the image above, the border on each side is set to1and the padding is set to7. These values can be changed by double clicking the values in the box and assigning them new numbers, or using the up or down arrow keys on your keyboard.

Note:If you inspect an element and find that the border is set to-, adding a numerical value will not make a border appear. The border color, style, and width must be set in the CSS document in order to see the border.

Exercise II: Modify a Website’s Box Model Dimensions

Pick up where you left off in Exercise 1.

  • Double click the top padding of the element.
  • Use the up and down arrows to adjust the element’s padding. Observe how the appearance changes on the web page.
  • Change the left margin to 200. Observe how the element’s appearance changes.

Rememberthe changes you make in DevTools are not saved. If you are using DevTools to make adjustments to a personal project, make sure to adjust values in the HTML and CSS documents.

'The Codecademy Team, composed of experienced educators and tech experts, is dedicated to making tech skills accessible to all. We empower learners worldwide with expert-reviewed content that develops and enhances the technical skills needed to advance and succeed in their careers.'

30% Free Preview Reached · Unlock Remaining 70%

Complete Payment to Unlock Full Guide & Source Code

You are viewing the 30% preview. Join TopCourseAI Pro to unlock the remaining 70% of this article, unblur all code snippets, and gain full access to all 412 technical projects and guides.

✓ Full Access to All 160+ Projects
✓ Instant Blur Removal Everywhere
✓ Production Source Code & Blueprints
✓ All Future Deep Dives Included
Instant Unhindered Activation ·
End of Preview · Unlock Complete Blueprint & Source Code

Ready to access the complete step-by-step tutorial?

Gain full unhindered access to all 412 technical projects and guides, unblur all source code snippets, and download runnable scripts.

Production AI Blueprints

Ready to build production-grade AI systems?

Enjoyed this guide? Continue exploring our library of 166+ production blueprints, multi-agent swarms, and autonomous agent systems with 100% unblurred, executable source code.