Common Debugging Tools
Common Debugging Tools
Debugging is a lot easier when you have the right tools. Here is a list of the most common debugging tools used by professional developers every day.
1. IDE Debuggers
Built-in tools in your editor (VS Code, IntelliJ, etc.) that allow you to set breakpoints, step through code, and inspect variables.
- Learn them if: You’re writing any kind of backend or desktop application.
2. Browser Developer Tools
Every modern browser (Chrome, Firefox, Safari) has a suite of tools built-in.
- Console: Where you see logs and errors.
- Network Tab: Where you see all API calls and image requests.
- Sources/Debugger: Where you set breakpoints in your frontend JavaScript.
- Elements: Where you see and edit your HTML/CSS in real-time.
3. Postman / Insomnia
Tools for testing and debugging API calls outside of your application code. They allow you to manually send requests and see the exact response.
- Learn them if: You’re building or using an API.
4. Sentry / Bugsnag
Error tracking tools that “listen” for crashes in production and send you a detailed report when they happen.
- Learn them if: You have real users.
5. Datadog / New Relic
Performance monitoring tools that show you CPU, memory usage, and slow database queries across your entire system.
- Learn them if: Your app is slow.
6. DBeaver / TablePlus
Database GUI tools that allow you to see and search your data without writing complex SQL commands in the terminal.
- Learn them if: You’re using a database.
Comparison Table
| Tool | Purpose | Best For… |
|---|---|---|
| Debugger | Pause and Inspect | Finding logical errors in code |
| Network Tab | Inspect API calls | Debugging connection issues |
| Logs | Record events over time | Debugging issues that already happened |
| Postman | Test API endpoints | Designing and testing APIs |
| Sentry | Alert on crashes | Fixing production bugs quickly |
Real-World Scenario: The “Unknown Data” Bug
The Problem: Your frontend is showing “null” for a user’s name.
The Tools You Use:
- Network Tab: Check the API response. You see
{"name": null}. The frontend is correct! - Postman: Call the API manually with the same user ID. You still see
null. The bug is in the backend! - IDE Debugger: Place a breakpoint in the backend’s
getUser()function. You see that the database query is returning an object, but you’re accidentally returning the wrong variable.
Common Beginner Mistakes
- Not Learning Your Tools: Spending hours using
console.log()because you’re “too busy” to learn how to use a debugger. - Using Too Many Tools at Once: Start with the simplest tool (like the Console) and only move to more complex tools if you need more information.
- Thinking the Tool will “Fix” the Bug: A tool only gives you information. You still have to use your brain to find and fix the bug!
Advice for Beginners
- Learn VS Code Debugger First: It’s the most versatile tool and works for many languages.
- Bookmark the “Network” Tab: You’ll use it 50 times a day.
- Keep Your Tools Open: Always have your Developer Tools or your logs open while you’re developing, so you see bugs as soon as they happen.
Next Lesson
Finally, let’s look at the mistakes you should avoid: