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  • Tutorials
    • The AI Iteration Loop for Deploying Reliable Agents with LangGraph
    • Using LaunchDarkly feature flags and Experimentation with Wordpress
    • Migrate a Hardcoded LangGraph Agent to LaunchDarkly AgentControl in 20 Minutes
    • Offline Evaluation of RAG-Grounded Answers in AgentControl
    • Beyond n8n for Workflow Automation: Agent Graphs as Your Universal Agent Harness
    • Catch your first silent AI failure with Vega AI in under 10 minutes
    • Evaluate LLM code generation with LLM-as-judge evaluators
    • OpenTelemetry for LLM Applications: A Practical Guide with LaunchDarkly and Langfuse
    • Use LaunchDarkly Agent Skills in Claude Code and Cursor
    • Detection to Resolution: Real World Debugging with Rage Clicks and Session Replay
    • Compare AI orchestrators: LangGraph vs Strands vs OpenAI Swarm
    • Building a data extraction pipeline with LaunchDarkly
    • Day 12 | 🎊 New Year, New Observability
    • Day 11 | ✉️ Letters to Santa: What engineering teams really want from Observability in 2026
    • Day 10 | Why observability and feature flags go together like milk and cookies
    • Day 9 | 👻 The Three Ghosts Haunting Your AI This Holiday Season
    • Day 7 | 🎄✨The Rockefeller tree in NYC: SLOs that actually drive decisions
    • Day 6 | 💸 The famous green character that stole your cloud budget: the cardinality problem
    • Day 5 | 🧹 Using a Popular Tidying Method to Consolidate Your Observability Stack
    • Day 4 | ❄️ Tracing the impact of holiday styling in your Node.js app
    • Day 8 | 🎁 Observable Multi-Modal Agentic Systems
    • Day 3 | 🔔 Jingle All the Way to Zero-Config Observability
    • Day 2 | 🎅 He knows if you have been bad or good... But what if he gets it wrong?
    • Collecting user feedback in your app with feature flags
    • Day 1 | 🎄 Observability Under the Tree: What Changed in 2025
    • Build a User Frustration Detection & Response System
    • When to Add Online Evals to Your AgentControl
    • Detecting User Frustration: Understanding Rage Clicks and Session Replay
    • AgentControl config CI/CD Pipeline: Automated Quality Gates and Safe Deployment
    • A Deeper Look at LaunchDarkly Architecture: More than Feature Flags
    • Add Observability to Your React Native App in 5 minutes
    • Smart AI Agent Targeting with MCP Tools
    • Build a LangGraph Multi-Agent System in 20 Minutes with LaunchDarkly AgentControl
    • Snowflake Cortex Completion API + LaunchDarkly SDK Integration
    • Using AgentControl to review database changes
    • How to implement WebSockets and kill switches in a Python application
    • 4 hacks to turbocharge your Cursor productivity
    • Create a feature flag in your IDE in 5 minutes with LaunchDarkly's MCP server
    • Observability for Your Go ORM: OpenTelemetry Integration with GORM
    • The complete guide to OpenTelemetry in Next.js
    • How to instrument your React Native app with OpenTelemetry
    • The complete guide to OpenTelemetry in Python
    • Monitoring Browser Applications with OpenTelemetry
    • How to Use OpenTelemetry to Monitor Next.js Applications
    • What is OpenTelemetry and Why Should I Care?
    • Distributed Tracing in Next.js Apps
    • Tracing Distributed Systems in Next.js
    • Real-time Monitoring in Django: Essential Tools and Techniques
    • DeepSeek vs Qwen: local model showdown featuring LaunchDarkly AgentControl
    • Application Tracing in .NET for Performance Monitoring
    • The Ultimate Guide to Ruby Logging: Best Libraries and Practices
    • Using Materialized Views in ClickHouse (vs. Postgres)
    • Filtering and Sampling LaunchDarkly Ingest
    • How to Set Up Your Production AWS MSK Kafka Cluster
    • Publishing an NPM Package with Private pnpm Monorepo Dependencies
    • How To Use The Chrome Inspector & Debugger
    • 3 Levels of Data Validation in a Full Stack Application With React
    • The power of the monorepo: Keep your fullstack app in sync!
    • Compression: The simple, powerful upgrade for your web stack
    • Video tutorials
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On this page
  • Why Use Chrome DevTools
  • How to Open Chrome DevTools
  • The Chrome DevTools Tabs
  • Elements
  • Console
  • Sources
  • Network
  • Application
  • Chrome Devtools — Your New Best Friend
Tutorials

How To Use The Chrome Inspector & Debugger

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Published November 1, 2022

portrait of Oyinkansola Awosan.

by Oyinkansola Awosan

Chrome Developer Tools, more popularly known as Chrome DevTools, is a toolkit for web developers built into the Google Chrome browser.

Web development can be arduous depending on what is being built, the tools used, and the expertise of the developer involved. As a result, any help a web developer can get is welcome.

The Chrome DevTools provides a set of tools that enable developers to edit their web pages in real-time, diagnose problems quickly, debug their code, and measure and optimize the performance of their web pages.

Though it is primarily designed for developers, it can also be used by casual users to get insights into how a webpage works.

Whether you’re a seasoned web developer or just getting started, Chrome DevTools is a valuable tool that can help you build better websites.

Why Use Chrome DevTools

With the toolkit being embedded in the browser, Chrome DevTools provides developers with powerful and efficient tools which can be used to inspect and edit code without switching tabs.

The Chrome DevTools provides developers with simulations that enable them to see the performance of their website across different devices and browsers. This is extremely useful for fixing potential problems and optimizing the website for all users. The device mode tests across various devices, and the browser mode tests across various browsers.

It also allows developers to measure page performance, analyze network activity, and track down memory leaks. In short, Chrome DevTools is an indispensable tool for any web developer.

While it may seem daunting at first, the Chrome DevTools documentation is actually quite helpful. And once you get the hang of it, you’ll wonder how you ever developed without it.

How to Open Chrome DevTools

To open the Chrome DevTools by press Option + ⌘ + J (Mac) or CTRL + SHIFT + J,(Windows, Linux).

Once the DevTools are open, you should see a panel that looks like this:

Chrome DevTools panel after opening it with the keyboard shortcut.

Chrome DevTools panel after opening it with the keyboard shortcut.

Alternatively, can also left-click on the web page, and select the inspect option in the menu that comes up.

Right-click context menu showing the Inspect option to open Chrome DevTools.

Right-click context menu showing the Inspect option to open Chrome DevTools.

Usually, the DevTools space opens up in the Elements tab by default. However, there are a total of 10 tabs, each with its own purpose:

  • Element
  • Console
  • Sources
  • Network
  • Performance
  • Memory
  • Application
  • Security
  • Lighthouse
  • Recorder
  • Performance insights

Chrome DevTools showing all available tabs including Elements, Console, Sources, Network, and more.

Chrome DevTools showing all available tabs including Elements, Console, Sources, Network, and more.

For the purpose of this article, we will be focusing on 5 of these:

  • Elements
  • Console
  • Sources
  • Network
  • Application

The Chrome DevTools Tabs

Elements

The Elements panel is where you’ll do most of your work in the DevTools. This is where you can inspect and edit the HTML and inline CSS of the web page to inspect or edit. You can make changes to your code either temporarily or permanently and see the changes implemented immediately.

The Elements panel in Chrome DevTools for inspecting and editing HTML and CSS.

The Elements panel in Chrome DevTools for inspecting and editing HTML and CSS.

In the Elements tab, you can adjust buttons, spacing, images, and other HTML elements on the page, or even change the properties of an element.

The Elements tab allows you to edit the style and content of your page without affecting the source code, as any changes you make to your page will not be permanent once you refresh the page. This helps you to run tests and make decisions about making changes to the page as you are seeing it in real time.

In the Styles pane, you can add declarations and check if a class is applied to a particular element and the order in which all styles are applied.

The Computed pane can be a helpful way to check if your CSS classes are being overridden. If you’re expecting a certain class to be applied to your code, but it’s not appearing, the Computed pane can show you which class is actually being applied.

The Computed pane in Chrome DevTools showing applied CSS properties and box model sizing.

The Computed pane in Chrome DevTools showing applied CSS properties and box model sizing.

This can be especially helpful in troubleshooting sizing problems, as you can see exactly which property is causing the issue.

You can even add new elements to your web page under the Elements pane. To do this, click the “Add Element” button at the pane’s top. Here you can put in the HTML for the new element and click ‘OK” to see it added.

Console

The console tab is a powerful tool that every JavaScript programmer should be aware of. It basically supplies information about the interactive elements on your web page while allowing you to interact with the web page by writing JavaScript.

The console tab allows you to interact with your web page in real time, run, debug, and even test code snippets.

To debug with the console tab, you need to input a debugger into your code, refresh the page and create an event. Once you have done this, you will be redirected to the debugger console.

The console tab is particularly useful for debugging, as it allows you to spot bugs or issues much faster than if you were testing in your actual JS file.

If the code is now working according to what is expected with no issues, you can go ahead to copy it and put it into your actual JS file to make your changes permanent.

The Console tab in Chrome DevTools used for running and debugging JavaScript code.

The Console tab in Chrome DevTools used for running and debugging JavaScript code.

Get started with the console tab by writing JavaScript into the console, then click “Enter.” The Console will review the code you put in and return the result.

Overall, the Sources tab is a great way to get a closer look at the inner workings of your web page and make changes as needed. So if you’re ever stuck on a coding problem or just want to experiment with some new ideas, be sure to give it a try.

Sources

The Sources tab allows you to view and edit both the CSS and JavaScript code of your page.

To use it, simply select a file, and the contents will open up in the Editor pane. From there, you can make changes to your code and see them implemented in real time. The pages button at the top will show you what file you are currently inspecting.

One handy feature of the Sources tab is the ‘Filesystem’ button at the top, which lets you connect your file directly from your code editor to Chrome DevTools. This can be useful when you are confident about the changes you want to make, as it means that any change made in DevTools will automatically be saved in the source file.

However, it is essential to note that by default, any changes made in DevTools will not be reflected in your source code unless you connect your code editor to DevTools as well.

So if you want to make sure that your changes are saved, be sure to use this feature. Otherwise, your changes will be lost when you refresh the page.

The Sources tab in Chrome DevTools for viewing and editing CSS and JavaScript files.

The Sources tab in Chrome DevTools for viewing and editing CSS and JavaScript files.

The sources tab also allows you to see the values of variables and set breakpoints.

To set a breakpoint, simply select the line number you want to set a breakpoint on, put in the breakpoint conditions, and you’re good to go! This can be incredibly helpful when trying to pinpoint the cause of an error.

Network

The Network tab is a powerful tool that can help you identify and diagnose loading issues on your web page.

By selecting a resource, you can see detailed information about that resource, including the type of resource, when it was loaded, and how long it took to load.

The Network tab in Chrome DevTools showing resource loading details and timing information.

The Network tab in Chrome DevTools showing resource loading details and timing information.

This information can help identify resources that are taking longer than expected to load, which can indicate an issue with the server or the network.

Additionally, the Network tab can help you troubleshoot requests returning an error status code. If a status other than 200 is returned, that means there is an issue somewhere. And by troubleshooting these request errors, you can help ensure that your web page is loading smoothly and efficiently.

The Network tab shows the loads for the URL being viewed. This means you can get detailed information about what is causing the slowdown.

The Network tab displaying detailed load information for the current URL.

The Network tab displaying detailed load information for the current URL.

You can also use the Network tab to throttle network speed. This can be helpful when you’re trying to test how a website will perform on slower connection speeds. To throttle network speed, simply click the “Network throttling” button at the top of the panel and select the desired connection speed. And then simply click OK to apply the changes.

Application

The Application tab is a really handy tool that allows you to see what resources are being used by your web application, clear any web app data that you don’t need, and ensure it’s healthy.

To use the Application tab, simply select a resource under the Resources pane. This will bring up the storage details of that resource.

If you need to clear any web app data, you can do so by selecting the ‘Clear storage’ option from the menu. This includes cache, cookies, local storage, and anything else that makes up the data of your web application.

The Application tab in Chrome DevTools showing storage, cache, and web app data resources.

The Application tab in Chrome DevTools showing storage, cache, and web app data resources.

Chrome Devtools — Your New Best Friend

Knowledge of how to use Chrome Devtools is definitely a must-have for web developers as the toolkit is not only versatile but it is also easy to use.

If you are a web developer (or aspire to be one), then it is time for you to up your game and learn how to use Chrome Devtools. This powerful tool can help you speed up your development process, make it easier to debug any issues, and boost your productivity.

And if you’re not a web developer but want to know more about what’s going on under the hood of your web applications, Chrome Devtools can also help you out.

If you’re not using it yet, make sure to add it to your arsenal of tools — you won’t regret it!