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JS
JavaScript error

TypeError

The JavaScript exception "null (or undefined) has no properties" occurs when you attempt to access properties of null and undefined. They don't have any.

Reference entryJavaScriptFetched
This is a reference entry from MDN Web Docs. A full explanation with fixes has not been written yet.

The error messages

TypeError: Cannot read properties of undefined (reading 'x') (V8-based)
As listed by MDN Web Docs
TypeError: Cannot destructure 'x' as it is undefined. (V8-based)
As listed by MDN Web Docs
TypeError: Cannot destructure property 'x' of 'y' as it is undefined. (V8-based)
As listed by MDN Web Docs
TypeError: null has no properties (Firefox)
As listed by MDN Web Docs
TypeError: undefined has no properties (Firefox)
As listed by MDN Web Docs
TypeError: undefined is not an object (evaluating 'undefined.x') (Safari)
As listed by MDN Web Docs
TypeError: Right side of assignment cannot be destructured (Safari)
As listed by MDN Web Docs

Details

Category
TypeError
Severity
error
Runtime
both

Related errors

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Source: MDN Web Docs. Data fetched 2026-09-25T01:48:37.274Z.