How to Fix the "structuredClone is not defined" Error in Node.js

Last updated on March 14, 2023

The “structuredClone is not defined” error occurs when you try to use the structuredClone()/ method in JavaScript, but it’s not defined.

The "structuredClone is not defined" error occuring in a terminal.

To fix it, install Node.js 17 or a newer version. Once you've updated Node.js, you can use structuredClone() to clone objects with all their properties and methods.

What causes the “structuredClone is not defined” error?

If you try to use the structuredClone() method in a script that's running with a Node.js version lower than 17, you will encounter this error.

The structuredClone() method is used to create a deep copy of an object. It’s a built-in function in JavaScript and is used to clone an object with all its properties and methods.

But when the structuredClone() method is not defined, it means that the server environment doesn’t recognize the function and cannot perform the action.

Fix: update Node.js

To fix the “structuredClone is not defined” error in JavaScript, you need to install Node.js 17 or a newer version. If you’re using an older version of Node.js, it will throw an error when you try to use structuredClone().

Install from website

To download Node.js, visit the official website and opt for the LTS version, as it offers superior stability. As of the time of writing this article, the most recent LTS release of Node.js is v18.15.0.

The Node.js download page on the official website.

Install with Chocolatey

If you’re using Chocolatey, Node.js is available as the nodejs package, meaning you can easily install it in a terminal using the following command.

# Use current LTS version

choco install nodejs --version=18.5.0

After installing, you can use the structuredClone method to clone an object:

const obj = { name: 'Mike', friends: [{ name: 'Sam' }] };
const clonedObj = structuredClone(obj);

console.log(obj.name === clonedObj);  // false
console.log(obj.friends === clonedObj.friends);  // false

Key takeaways

If you get the "structuredClone is not defined" error when using the structuredClone() method in JavaScript, it means that the method is unavailable. To fix the problem, update your Node.js to a version newer than 17. You can get the latest version from the official Node.js website or install the nodejs package using Chocholatey.

Try Coding Beauty AI Assistant for VS Code

Meet the new intelligent assistant: tailored to optimize your work efficiency with lightning-fast code completions, intuitive AI chat + web search, reliable human expert help, and more.