A lot of web development tools are integrated into browsers today. Popularly known as add-ons or extensions, these tools are not just for web development, but also serve a lot of other functions, of which debugging is one of the most prominent. These tools make your life a lot easier and help you in inspecting and analyzing possible issues with the CSS, HTML, and JavaScript used in the code. In this post, we have listed the top twelve browser debugging tools. Not only can these help you debug and inspect your code, but also inspect the HTTP headers, access various FTP source files, and evaluate the accessibility of the web page.

1. Firefox Developer Tools

Firefox Developer Tools is an amazing set of tools with a lot of features to examine, explore and debug websites and web pages. You can easily view and modify the page HTML and CSS using this. Apart from that, with its inbuilt JavaScript debugger, you can stop, step through examine and modify the JavaScript running in a page. The Storage Inspector lets you inspect cookies, local storage, and session storage present in a page. 

2. Chrome Developer Tools

Chrome Developer Tools is a set of web developer tools inbuilt to Google Chrome. It helps you edit pages and remove errors in the code. "DevTools for beginners" is an amazing tool to learn the fundamentals of web development. Explore the tool and easily view and change a page’s styles, debug JavaScript, and even optimize the speed of the website.

3. Web Developer

Web Developer is an extension for Firefox and a few other browsers which adds a toolbar with a lot of options and features for debugging and inspecting web pages. This tool is especially helpful for working with large CSS files and projects that you may be unfamiliar with. It even has a built-in feature for validating the syntax of the page and help you locate the possible errors.

4. Safari Developer Tools

Make sure that your website works well with all the major web browsers using Safari Developer Tools. Safari comes equipped with Web Inspector, a powerful tool that simplifies the job of modifying, debugging, and optimizing a website for optimal performance and compatibility on different platforms. Its responsive design mode helps you get a preview of your web pages for various screen sizes, orientations, and resolutions.

5. Internet Explorer Web Edge (Developer) Toolbar

Internet Explorer Web Edge Developer Toolbar is the tool for you if you are looking for something that resembles Firebug in functionality. Using this tool, you can easily edit the web page’s DOM and HTML directly in the browser. It also lets you change and edit DOM elements to inspect what happens as you perform predefined actions or modify the code. Apart from that, you can use this tool to test and debug JavaScript with the IE Web Developer Toolbar.

6. Fiddler

Fiddler is an extension of Internet Explorer that lets you debug web applications and analyze a web page’s HTTP traffic. It lets you set up breakpoints and has a lot of other features useful for debugging. This tool is quite extensible and even lets you create your own scripts to perform useful functions.

7. Open Dragonfly

Open Dragonfly is a popular web development tool integrated into the web browser Opera. You can monitor network traffic, edit colors, view the DOM, and debug JavaScript. You need to download it once, but it then functions in offline mode, too. This is a cross-platform operating system developed by Opera Software.

8. DebugBar

DebugBar is a free tool for personal and educational use that helps you in debugging. It is an in-browser extension for Internet Explorer. You can send a web page screenshot via email and view both the original and interpreted code using this tool. It also has a color picker and a Console API. It helps you gain some quick and easy information using a command line interface.

9. YSlow

YSlow is a tool that helps you analyze web pages in order to understand why they are running slow. It works on Yahoo’s rules for high-performance websites and displays various relevant statistics for a page. Apart from that, it also gives suggestions for improving the performance of web pages and summarizes the page’s components.

10. HTTPWatch

HTTPWatch is yet another traffic viewer and debugger, quite similar to Fiddler in its working and approach. Generating request level time charts, decryption of HTTPS traffic to assist debugging, exporting captured data to XML and CSV formats are some of the prominent features of HTTPWatch. Its basic edition is free, but it has a professional and advanced version, too.

11. Live HTTP Headers

Live HTTP Headers is actually a Firefox extension that lets you inspect HTTP request and response headers. You can debug your web applications by exploring the HTTP headers with the help of this tool. Apart from that, the tool helps you obtain information about the website’s server and analyze cookies sent to the client while requesting a particular page.

12. Venkman JavaScript Debugger 

Venkman JavaScript Debugger is available as an add-on and helps you in debugging complex JavaScript and troubleshooting. You can interact with the debugger using the command line interface given by the console view. The Stack View feature of the tool lets you step through active functions when they reach the breakpoint.