Welcome to Coding Beez Learn at your own pace with structured courses designed for students and professionals. Find out more!

CodingBeez Logo

JSON.stringify() returns empty object.

JSON.stringify() Returns Empty Object for Error
  • Prakash Pradhan By Prakash Pradhan
  • codingBeez_calendar Jan 31, 2026
  • codingBeez_bookmark NodeJS
  • codingBeez_comments 0 Comments

JSON.stringify() returns empty object.

While working with JavaScript or Node.js, developers often face a confusing issue: when trying to stringify an Error object using JSON.stringify(), it returns an empty object {}.

json stringify returns empty object

This behavior raises several common questions:

Q. Why does JSON.stringify return {} for Error objects?
Q. Why doesn’t JSON.stringify throw an error for Error objects?
Q. Why does JSON.stringify not work inside a catch block?

In this article, we’ll break down why this happens and how to correctly serialize Error objects for logging, APIs, and debugging.

What Is JSON.stringify()?

JSON.stringify() is a JavaScript method that converts a JavaScript object into a JSON string. It is commonly used when sending data from a client to a server or when logging structured data.

JSON.stringify(obj);

How Does JSON.stringify Work?

When JSON.stringify() is called, it converts only the enumerable own properties of an object into JSON.

const obj = {
  name: "Alex",
  age: 20
};

console.log(JSON.stringify(obj));
// {"name":"Alex","age":20}

This works perfectly because both properties are enumerable. However, if an object contains only non-enumerable properties, JSON.stringify() has nothing to serialize.

What Is a Non-Enumerable Property?

A property is non-enumerable if it does not appear in:

  • Object.keys()
  • for...in loops
  • JSON.stringify()
const obj = {};

Object.defineProperty(obj, 'hidden', {
  value: 'secret',
  enumerable: false
});

console.log(JSON.stringify(obj)); // {}

Since the property is non-enumerable, it is ignored during serialization.

Why JSON.stringify Returns {} for Error Objects

In JavaScript, Error objects are designed with non-enumerable properties.

Important properties such as:

  • message
  • name
  • stack

are intentionally marked as non-enumerable. As a result, JSON.stringify() finds nothing to serialize and returns {}.

Example: JSON.stringify in a catch Block

try {
  throw new Error("Something went wrong!");
} catch (err) {
  console.log(JSON.stringify(err)); // {}
}

This is expected behavior and not a bug in JavaScript.

Solution: How to Properly Serialize an Error

Option 1: Manually Extract Error Properties

try {
  throw new Error("Something went wrong!");
} catch (err) {
  const errorDetails = {
    name: err.name,
    message: err.message,
    stack: err.stack,
  };

  console.log(JSON.stringify(errorDetails));
}

Option 2: Create a Reusable Helper Function

function serializeError(error) {
  return {
    name: error.name,
    message: error.message,
    stack: error.stack,
    ...(error.code && { code: error.code }),
    ...(error.cause && { cause: error.cause }),
  };
}

// Usage
console.log(JSON.stringify(serializeError(err)));

This approach is ideal for logging systems, APIs, and centralized error handling.

Best Practices

  • Never rely on JSON.stringify(error) directly
  • Always extract error properties manually
  • Use a helper function for consistency
  • Include stack only in non-production logs if needed

By following these practices, you’ll avoid silent logging issues and gain better visibility into runtime errors.

I hope this article helps! Feel free to comment with suggestions or improvements.

← –frozen-lockfile CI Build Error: “Your l... Converting circular structure to JSON
Prakash Pradhan

Prakash Pradhan

Sr. Software Engineer

Senior Software Engineer with 10+ years of experience in designing and scaling distributed systems and full-stack applications. Experts in optimizing system performance, and delivering high-impact technical solutions across the entire software development lifecycle.

Comments

No comments yet.

You need to login to comment

Related Posts

Converting Circular Structure to JSON in JavaScript
Converting circular structure to JSON

This article explains circular reference errors in JSON.stringify and provides practical s...

Base64 Encode and Decode in Node.js – Complete Guide
Base64 Encode/Decode a value in Nodejs

This article explains Base64 encoding and decoding in Node.js using simple examples. It co...

-bash: nvm: command not found — How to Fix
-bash: nvm: command not found

This guide explains why the "-bash: nvm: command not found" error occurs on macOS and prov...

Recent Posts

Categories

Tags