How do you handle errors when using `async/await`?

You can use a try/catch block around an await statement to catch errors that occur within the awaited Promise.

javascript

Difficulty: 5/10

Topics: try/catch, promise rejection, error propagation

0-2 years experience

1
You need to fetch user data with fetch and async/await. How would you catch a network error and return a default object?
2
If an async function throws inside a try block, what does the caller receive if you don't use try/catch?

2-5 years experience

1
We have a function that calls two async services sequentially. It sometimes fails on the second call, leaving the first call's side effects persisted. How would you restructure error handling to ensure consistency?
2
During debugging you notice an unhandled promise rejection warning even though you wrapped the await in try/catch. What could cause that?

5-8 years experience

1
Our microservice layer uses async/await throughout and we need a centralized way to log and transform errors before they bubble up. How would you design such a mechanism without losing stack traces?
2
When scaling to thousands of concurrent requests, what impact does using try/catch in every async handler have on performance, and how would you mitigate any overhead?

8+ years experience

1
We are migrating a legacy callback‑heavy codebase to async/await across multiple teams. What strategy would you use to enforce consistent error handling patterns and avoid silent failures?
2
How would you integrate async/await error handling with a distributed tracing system to ensure errors are captured across service boundaries?

❓Can you walk me through how the error propagates back to the caller in your example?
❓What are the trade‑offs between handling errors locally with try/catch versus a global error handler?
❓How would you test that your error handling behaves correctly under network failures?