All 10 Error Handling questions
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JavaScript › Error Handling

What does the finally block do?

Beginner

Answer

finally always runs after try/catch, whether or not an error was thrown or caught, and even if the try block returns early — making it ideal for cleanup code that must always execute.
function readFile() {
  openFile();
  try {
    return process();
  } finally {
    closeFile(); // always runs
  }
}
Real-world example Ensuring a loading spinner is hidden whether an API call succeeds or fails.

Common follow-ups: Does a return inside finally override a return from try?

Async Iterators & Streams
All 10 Error Handling questions