JavaScript

Error Handling in Async Code

Don't let errors break your app! Learn robust error handling patterns for asynchronous JavaScript.

By TechCoder TeamLast updated: 2026-06-02
In a Nutshell

Don't let errors break your app! Learn robust error handling patterns for asynchronous JavaScript. This hands-on tutorial focuses on practical implementation of error handling in async code concepts.

Error Handling in Async Code

When code runs asynchronously (like fetching data), errors don't crash your app immediately—they happen in the background. If you don't catch them, you get "Unhandled Promise Rejections."

1. The try...catch Block 🛡️

With async/await, error handling looks just like synchronous code.

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Why use finally? It runs regardless of success or failure. Perfect for resetting UI states (like isLoading = false).

2. Handling Multiple Requests ⛓️

If you have multiple await calls, one try...catch can handle them all.

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3. Promise.all vs. Promise.allSettled 🌈

  • Promise.all: Fails if ANY promise fails. (All or Nothing)
  • Promise.allSettled: Waits for ALL promises, regardless of success/failure. (Best for independent tasks)
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4. Global Error Handler 🌍

As a last resort, you can catch errors that you forgot to handle.

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AI Mentor

Confused about "Async error handling, try/catch, Promise.allSettled, and global handlers"? Ask our AI mentor for a simplified explanation.

Quiz

Quiz

Question 1 of 4

What block runs regardless of success or failure?

try
catch
finally
then

Key Takeaways

try...catch wraps risky async code.
finally handles cleanup (loading states).
Promise.allSettled is safer than Promise.all for mixed results.
Global handlers catch what you miss.

What's Next?

Let's finish this module by exploring powerful Browser APIs like Geolocation and Clipboard!

Keep coding! 🚀