referenceerror: window is not defined, how to solve
Find out how to fix the error referenceerror: window is not defined
Here’s how to fix the “referenceerror: window is not defined” error that you might have in Node.js or with a tool like Next.js.
window
is an object that’s made available by the browser, and it’s not available in a server-side JavaScript environment.
I describe the window
object is details in my extensive DOM Document Object Model guide.
With Node.js in particular there’s no way to workaround the problem - you must find the particular place where window
is used, and revisit the code to figure out why you are accessing the window
object.
You are running frontend code in a backend environment.
In Next.js you can fix this problem by wrapping the code you run in a conditional.
The code might be running in both situations - frontend, when you navigate to a page using a link, and server-side if you require server-side into your page, for example by running getServerSideProps()
.
In this case, you can limit the reference into a conditional that checks if the window
object is available, like this:
if (typeof window !== 'undefined') {
//here `window` is available
}
And this will fix your problem, since you only run anything inside the conditional in a browser environment.
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