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Firebug Alternatives: 10 Best JavaScript Debugging Tools

Firebug Alternatives

Stephen Cooper UPDATED: March 27, 2023

If you are looking for Firebug. You are too late: it is no more. However, we have other JavaScript debugging tools for you to try.

Firebug was an open-source debugging tool that also enabled the editing and monitoring of a website’s JavaScript, HTML, DOM, XHR, and CSS elements. It was a great service for those who engaged in the development of websites, those who needed to test new code, and those who had the responsibility for ongoing monitoring and maintenance of sites. It was a useful utility for DevOps environments for websites. What made it even better was that it was completely free to use.

The Firebug system operated as an extension for Mozilla Firefox browsers and was a project of the Mozilla organization. Its testing capabilities extended to security and performance analysis, so it was more than just a code debug system.

Firefox 57, released in late 2017. This version of the browser had some major changes. One of those was the removal of compatibility with XUL add-ons. XUL was another free product that was developed under the aegis of Mozilla. The full name of the system is XML User Interfaced Language, which, unfortunately, was the development code used for Firebug. So, because of this change to Firefox, Firebug, which had no standalone version, ceased to be useable.

Alternatives to Firebug

Firebug offered an impressive range of services. It is a difficult package to beat. The fact that it was free makes the task of finding a replacement for Firebug even harder. However, there are some good solid options out there.

The field of website testing and DevOps tools has expanded strongly in recent years. There are some interesting options available, so it is possible to find a tool that will prove to be alternatives to Firebug. However, it might be necessary to take on several tools in order to match all of the functionality offered by Firebug. In this review, we will concentrate particularly on JavaScript debugging tools.

To get close to Firebug’s operating methods, the best systems to look at are those that are integrated into Web browsers and so are free and operating system-neutral. There are also free JavaScript debuggers that are offered as extensions to Web browsers, which is exactly how Firebug functioned. We also added a couple of paid products to give you a rounded view of the current market for JavaScript debuggers.

Here is our list of the ten best Firebug alternatives that are JavaScript debugging tools:

  1. The Firefox JavaScript Debugger The successor to Firebug, Firefox Developer tools, was integrated into the Firefox Web browser in a range of utilities. The JavaScript Debugger is part of that suite of tools and is free to use.
  2. Google Chrome Dev Tools A suite of tools to support Web development and testing that is integrated into the Google Chrome Web browser and is free to use, including a JavaScript debugger.
  3. Opera Chromium Dev Tools In a similar scenario to Mozilla Firebug, Opera dropped its package of developer tools, called Dragonfly, and integrated its utilities into the browser menu.
  4. Edge Developer Tools Microsoft’s Web developer tools, including a JavaScript console, are integrated into the Edge browser and are free to use.
  5. Safari Developer Menu The Safari browser has a suite of free developer tools, including the JavaScript Console, which need to be activated before they are available.
  6. Flow A static type checker for JavaScript code that is open source and free to use. Installs on Linux.
  7. Omnibug An analyzer for Web marketing tools that can be used as part of a QA process when assessing the impact of browser-based applications. Available as a free add-on for Chrome, Firefox, Edge, Opera, Safari, Brave, and Vivaldi.
  8. SplineTech JavaScript Debugger A standalone debugging tool supplied directly by the programmer that wrote it. Runs on Windows.
  9. Raygun Error Monitoring A paid cloud-based service that integrates into a web page with a snippet.
  10. JS Bin A free, online Web development tool that includes a JavaScript debugger. Set up a paid account to get extra benefits.

The top JavaScript debugging tools

You can read more about each of these options in the following sections.

1. The Firefox JavaScript Debugger

Given that Firebug was such a useful collection of development, testing, and monitoring tools, you would think it strange that Mozilla didn’t update the code for those services so that they would continue to work with the new version of the Firefox browser. That upgrade didn’t happen because the browser’s project team had already integrated the best features of Firebug into the browser itself. So, all of those tools are still available, just not as a separate plug-in with a distinct name.

The JavaScript Debugger of Firefox is available from the Tool’s menu in the top menu of the browser. One of the options on that menu is labeled Web Developer and this opens up a sub-menu of utilities, which includes the JavaScript Debugger.

The debugger lets you run through JavaScript code step by step to help you spot errors. The code step view allows you to drill through to the code of functions as they execute or you can choose to stay in the main body of the program to watch the results of the function come back. The tool lets you enter breakpoints, conditional breakpoints, and write output to log files.

The debugger is also able to examine CSS and HTML code Other utilities in the Web Developer suite of Firefox include the Page Inspector, which acts as a Web page editor, and the Web Console, which gives access to log files. The system also includes a network monitor and a Web page performance analyzer.

2. Google Chrome Dev Tools

Google Chrome includes a suite of free Developer Tools, just like those in the Firefox browser. These are also free and they are bundled into the standard Chrome browser.

In order to debug the code, you just run the page that it contains. You can pause the execution and open a side panel that shows the code in play and the point that execution has reached. You can rewind and click on a specific line to get it to run.

The debugger offers a list of events that you can activate a pause on and then click on step by step so you can watch the code execute in slow motion. The step-through shows the JavaScript program and highlights the current line as execution progresses. It also jumps through to function code when it is called.

The tabbed interface of the debugger lets you jump to log file viewing in the console or see network actions and application performance analysis without losing your place in the code walk-through.

3. Opera Chromium Dev Tools

The opera development team used to run a separate project for a development tool suite, called Dragonfly. Like Mozilla, Opera decided to integrate these tools into its browser. These are now called Chromium Dev Tools and they are free to use. In fact, these are exactly the same tools that you can access in Google Chrome.

The developer tools in Opera can be accessed by pressing Control-Shift-C. this shows a code view of the current page, so in order to debug JavaScript, you would need to load the page that contains it. To get to the JavaScript debugger, you have to click on the three dots menu at the end of the page inspector’s menu strap and then select More Tools and click on JavaScript Profiler from the sub-menu.

The JavaScript Profiler records the time taken to execute each step in your code, which can show you where inefficiencies lie. Other tools in the developer’s bundle include a network monitor and an application performance analyzer.

4. Edge Developer Tools

Microsoft Edge includes free developer tools that are also exactly the same as those in Google Chrome. As in Chrome, press Control-Shift-C to open the code debugger side panel. They can also be reached by looking in the three dots menu, selecting More Tools, and then clicking on Developer Tools. As explained in the Opera section above, there is also a JavaScript Profiler available from the three dots menu within the Developer side panel.

5. Safari Developer Menu

The Safari browser is available for macOS and iOS devices. It includes developer tools, but you have to activate the Developer menu before you can access them. Once you’re set-up, you can access the Web inspector, which is an impressive performance monitor.

The tabbed interface of the Web Inspector includes a section for a debugger. This lets you observe JavaScript as it runs, set breakpoints, and advance execution line by line. Other utilities in the developer interface include a live event tracker that covers network and application performance and an HTML viewer.

6. Flow

Flow is a development environment for JavaScript. It can spot errors as they are written and suggests improvement to programs. The environment also includes a testing system and a code library manager with version control and file protection services.

The flow testing system can track data during test runs and expose current values as each step of the JavaScript code works on them. This is a great tool for DevOps environments and it is able to integrate with typical development and operations planning tools. Flow is free to use and it installs on Linux.

7. Omnibug

Omnibug is an add-on for browsers and it is available for Chrome, Firefox, Edge, Opera, Safari, Brave, and Vivaldi for free. This system focuses on the performance of marketing tools that operate from within your own Web pages. Although this isn’t exactly a JavaScript debugger, it has a feature that assesses all the code built into a Web page or Web application to assess it for errors. The emphasis with this tool is on error-checking bought-in applications and services.

8. SplineTech JavaScript Debugger

SplineTech JavaScript Debugger is a paid tool that is marketed by the programmer who developed it. Daniel Aroustamoff wrote the first version of this tool in 1999 and he has been updating the system ever since.

This is a software package that installs on Windows. It uses Internet Explorer as its front end and so adapts the standard browser to act as a source code viewer and debugger for JavaScript. The tool allows you to set breakpoints to stop execution at a specific piece of code. You can then step through the code and rewind to look at the behavior of the system as your JavaScript runs.

9. Raygun Error Monitoring

Raygun Error Monitoring and Crash Reporting is a cloud service that monitors the performance of Web pages constantly and spots errors in the code while it is live. The client activates the service by including a snippet from Raygun on the page to be monitored. This code acts as an agent for the Raygun analysis engine. Raygun Error Monitoring is available for a 14-day free trial.

The tool keeps running and is active on your pages as long as they can be contacted over the internet. This means you can use the tool while the code is still in development and when it gets to the testing phase before it goes live.

10. JS Bin

JS Bin is a website that includes a JavaScript editor and tester right on the Home page. There is no privacy in this free tool, which makes it a good tool for collaboration – you just give the URL to colleagues and let them see the code as you write it, so they can make suggestions.

The interface shows an HTML wrapper, which can also be expended, so you can test a whole page through its HTML and JavaScript elements.

To take your code private and get the ability to save work in progress, you need to open up a paid account.

Firebug Alternatives FAQs

What are some popular JavaScript debugging tools?

There are many JavaScript debugging tools available, but some of the most popular ones include:

  • Chrome DevTools
  • Firefox Developer Tools
  • Microsoft Edge DevTools
  • Node.js Debugger
  • Safari Web Inspector

How do I use a JavaScript debugger in the browser?

The process of using a JavaScript debugger in a browser varies slightly between different browsers, but here are the general steps:

  • Open the developer tools in your browser (usually by right-clicking anywhere on the page and selecting "Inspect" or using a keyboard shortcut).
  • Navigate to the Sources tab.
  • Find the JavaScript file you want to debug and open it.
  • Set breakpoints in your code by clicking to the left of the line numbers.
  • Refresh the page or run the code that you want to debug.

The code will pause at the first breakpoint, and you can use the debugger to inspect the values of variables and step through the code.

Which is the best alternative to Firebug?

The best alternative to Firebug depends on your personal preferences and the type of projects you are working on. Some popular options include Chrome DevTools and Firefox Developer Tools.

Can I use Firebug in modern browsers?

Firebug is no longer maintained and is not compatible with modern browsers. If you are looking for a JavaScript debugging tool, you should use one of the alternatives mentioned above.

Do I need to install an extension to use a Firebug alternative?

No, you do not need to install an extension to use a Firebug alternative. Most modern browsers have built-in developer tools that you can use to debug your JavaScript code. To access these tools, you can usually right-click anywhere on the page and select "Inspect" or use a keyboard shortcut.