JavaScript is a very versatile scripting language that enables users to create dynamic pages. As of 2023, it is used as a client-side programming language by 98.2% of all websites in the world. It has truly become the de facto language for website development.
However, experienced JavaScript developers understand that it can sometimes be difficult to work with. Debugging JavaScript code is not usually straightforward, and you sometimes need advanced skills to find the issues. However, if you use top JavaScript debugging tools and scripts, you can easily fix issues and ship error-free JavaScript code in your build.
What Is JavaScript Debugging?
JavaScript debugging is a process in which the developers scrutinize JavaScript code to find syntax errors, style errors, and logical flaws. It is an exercise in which all the issues that may hamper the execution of a JavaScript program are listed and fixed.
This process has the following steps.
#1 Identifying the bug
This is the first step of the debugging process and is also called the bug detection step. Here, the bug is identified via error messages and notifications.
#2 Isolating the source of the error
Here the developers identify the portion of the code that is causing the error.
#3 Identifying the cause of the error
In this step, the code is checked to identify what line/function is passing that error message. Developers can also try to reproduce the error message.
#4 Fixing the issue
Once the location and source of the bug is identified, the next step is fixing it. There are many ways to fix an error. The developer usually uses all those approaches one by one and runs the code to see the final result. After choosing an approach, they deploy the code in production systems.
Why Is It Important to Debug JavaScript Code?
Debugging is an essential part of software development and is important for customer satisfaction. So let’s have a look at how debugging improves JavaScript projects.
#1 Reduces the errors
This is one of the most obvious advantages of debugging. It ensures that the code added to your repository works correctly and there are no errors.
#2 Saves time and development cost
Bugs can be hard to find after the code is deployed at the customer’s site. They also cost more to fix. This process allows developers to fix simple issues during the development phase instead of later when bugs can only be fixed by releasing a new project version.
#3 Security
Debugging can be used to fix security vulnerabilities and issues in the project. This is important since hacktivists often use code vulnerabilities to gain access to insecure systems.
#4 Code flow
Using breakpoints while debugging JavaScript can help developers identify the flow of the code. You can also use it to learn about the code’s different attributes, such as variables, data structures, methods, etc.
#5 Customer satisfaction
Shipping untested and error-prone code to the customer’s site can cause huge liability issues for the software development company.
What Are the Types of Debugging Tools Available?
Browser-Based Consoles
All major browsers, such as Chrome, Opera, Edge, and Safari, have built-in debuggers that allow developers to debug JavaScript through a console. You can also use them to inspect specific page elements and set breakpoints.
Standalone Debuggers
These are independent tools developers use to test and fix JavaScript code.
Node.js Debugger
This is a command-line debugging tool that developers can use to debug Node.js applications.
Debug Extensions
You can add JavaScript debugging extensions with code editors such as Visual Studio and Sublime Text to debug your code.
How to Choose the Right Tool
For any development, having the right tool for the job is half the battle. If you choose the correct tool, you can efficiently implement it into your infrastructure and use it for debugging your modules.
There are a few things you should keep in mind before selecting a JavaScript debugger for your project.
#1 Type of problem
Before selecting a tool, you need to understand your exact problem. For example, if you need to debug performance issues, you should use tools such as Airbrake or Raygun. On the other hand, if you’re looking to debug your style errors, you can use ESLint.
#2 Ease of use
Your debugging tool should have a simple learning curve and should be easy to use. Admins with limited QA knowledge should be able to use it to generate reports and schedule notifications. From a DevOps point of view, it should also be easy to integrate into your existing infrastructure.
#3 Customer Support
The tool you choose should have good after-sales support. It should come with online resources (e.g., videos, ebooks) and documentation to support its users.
There should also be an online community to help users in case they get stuck on a complex issue.
#4 Specific use case
Sometimes, developers have to choose a specific tool based on their use case. For example, if you are debugging a Node.js application, you should choose the Node.js debugger instead of a standalone one. This way, you won’t have to perform any tool integration or installation to debug your code.
Top 7 JavaScript Debugging Tools for 2024
#1 JS Bin
JS Bin is a free-to-use, open-source JavaScript debugging tool. It is often used by developers looking to make minor changes to small-scale projects. It was created for collaborative debugging, a process in which many developers get together to fix code issues. This tool has a whole suite of debugging features for updating JavaScript code.
It also enables you to log on to the website and troubleshoot scripts by other developers. However, any module you debug is technically exposed to the public unless you pay a fee.
Features
- This tool delivers real-time output to the user. You can also sync it to Dropbox for logging and analysis.
- It uses Codecast for sharing code in real time. The changed output can be seen through its live reload feature. Remote rendering can be used for rendering your output to a different device.
- Developers can export code to version and code maintenance tools such as GitHub.
- It also allows you to debug HTML and CSS code.
#2 Airbrake
Airbrake is a continuous-monitoring JavaScript debugger that provides real-time bug updates to the user. It also supports other languages such as PHP, Python, and Java. In addition, you can integrate this tool with quick notification tools such as Trello.
It has options for code snapshotting that allow developers to keep track of their software through breadcrumbs. Its performance monitoring options allow users to track performance data and monitor deployments done by CI/CD pipelines.
Features
- It is an easy-to-install and lightweight application.
- It has options for real-time alerts and contextual bug analysis. It also offers 24/7 monitoring of your tech stack to mitigate known issues.
- Airbrake notifiers are serverless and easy to use. They also support multiple programming languages and allow users to send alerts to the tool for analysis and assessment.
- This software also has options for workflow management and in-depth performance reporting. Developers can use Airbrake trackers to integrate the Airbrake error tracking service into their own tool.
#3 Firefox JavaScript Debugger
This JavaScript debugging tool allows users to locally test their JavaScript code on the Firefox browser. Users can also set breakpoints (conditional and XHR) for debugging and error handling.
It allows developers to add watchpoints for checking their code’s variables and expressions. It is free to use and easy to work with. QA engineers can also use it for performing cross-browser and accessibility testing.
Features
- Along with JavaScript, this tool also enables engineers to debug HTML and CSS code.
- It can be used to inspect cookies through the DOM property viewer.
- DOM mutation breakpoints allow developers to pause the code flow at the DOM node, which can then be checked on the page inspector. You can also check performance issues, responsiveness, and layout performance through this tool.
- It allows users to check missing features and debug worker threads.
#4 ESLint
ESLint is an open-source JavaScript debugging tool for analyzing static code. Engineers can also use it for checking coding syntax and quality issues such as typos and bracket errors.
In addition, you can use it to verify suspicious constructs and style errors. Developers can also add their own linting rules for text customization.
Features
- This tool has options for static analysis of code and can be used to fix style errors.
- It is highly flexible, can be added to most text editors, and is compatible with major operating systems such as macOS, Linux, and Windows.
- Most of the platform rules are pluggable and can be turned off and on as standalone rules.
- It also supports custom parsers and allows users to highlight errors.
#5 Raygun
This is a cloud-based tool for performance monitoring and debugging. You can also use it to collect data on end-user issues through crash reporting and bug feedback.
It can also monitor service-side performance and can perform end-user fault detection analysis. Furthermore, it can be integrated with third-party tools such as Jira for bug tracking and analysis.
Features
- This tool also supports other programming languages, such as PHP, .NET, and Ruby.
- It has filters that allow users to create code insights. You can also access contextual information and use it for real-time front-end monitoring.
- It is easy to install and use. Its subscription is divided into three options: application performance monitoring, real user monitoring, and error and crash reporting.
#6 Rollbar
Rollbar is a popular JavaScript debugger with options for deployment monitoring, exception reporting, and real-time error notifications. It is heavily used by QA professionals for error logging and bug analysis.
This tool provides users with bug-fixing suggestions along with the impact of bugs. You can also categorize bug reports and issue reports based on priority and impact.
In addition, it has workflow triggers that notify users if a module is shipped with known issues so that developers can resolve them before release.
Features
- It has options for bug finding, bug management, and bug telemetry.
- It enables users to set up real-time alerts and notifications for faster response.
- You can easily integrate it with workflows and VCS.
- It has options to send automated error responses through AI-assisted workflows. It can also run stack traces.
- The tool has built-in triggers to stop suspected deployments.
#7 GlitchTip
This is an open-source debugger that can be hosted locally. It allows developers to review, modify and rerun JavaScript modules.
You can use this tool for error tracking and logging through log messages and exceptions. It can also recognize security violations and application slowness issues.
Features
- Its dashboard is simple and easy to use. It can point out slow web requests, server transactions, and database calls.
- You can use this tool for uptime monitoring, as it will let you know if your website is not responding to calls. Uptime monitoring can be done by mimicking pings, GET and POST calls. You can also monitor heartbeats.
Once the data to the request is received, it compares it to an expected status set up by the user. If it doesn’t match, a notification is sent out to the development team saying that the app is down.
- It is very easy to set up alerts and manage the frequency of call-outs.
Conclusion
JavaScript debugging can be a difficult process. However, using the right tools and JavaScript best practices, you can easily mitigate errors and create an error-free build. Of course, as mentioned above, there are many different options available in the market for JavaScript debugging tools. You need to select the one that best fits your business requirements and use case.