JavaScript··8 min read

JavaScript Error Handling — try/catch, Custom Errors & Logging

Handle errors in JavaScript properly: try/catch/finally, Error classes, async errors, and user-friendly messages.

JavaScript error handlingtry catch javascriptjavascript errors

Error Handling Patterns in JavaScript

Unhandled errors crash apps and confuse users. Proper error handling separates junior from professional code.

Why JavaScript error handling Matters

Unhandled Promise rejections crash Node servers and leave users staring at spinners — proper errors separate hobby projects from production apps.

Use custom Error subclasses for domain failures; log stack traces server-side and show human messages client-side.

JavaScript error handling — Key Ideas You Must Know

  • try/catch/finally blocks
  • throw new Error('message')
  • Async errors need try/catch or .catch()
  • Custom error classes
  • Log server-side, show friendly UI messages

Practice JavaScript error handling with Free Lessons

Complete the JavaScript errors lesson on Sturdee.

Tip: Free interactive lesson: /tutorials/javascript/javascript_errors — practice JavaScript error handling with runnable code on Sturdee.

JavaScript Error Handling — FAQ

Frequently Asked Questions

Should I catch all errors?+

Catch where you can recover or add context. Let unexpected errors bubble in dev.