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---
title: ReferenceError
slug: Web/JavaScript/Reference/Global_Objects/ReferenceError
page-type: javascript-class
browser-compat: javascript.builtins.ReferenceError
---
{{JSRef}}
The **`ReferenceError`** object represents an error when a variable that doesn't exist (or hasn't yet been initialized) in the current scope is referenced.
`ReferenceError` is a {{Glossary("serializable object")}}, so it can be cloned with {{domxref("structuredClone()")}} or copied between [Workers](/en-US/docs/Web/API/Worker) using {{domxref("Worker/postMessage()", "postMessage()")}}.
`ReferenceError` is a subclass of {{jsxref("Error")}}.
## Constructor
- {{jsxref("ReferenceError/ReferenceError", "ReferenceError()")}}
- : Creates a new `ReferenceError` object.
## Instance properties
_Also inherits instance properties from its parent {{jsxref("Error")}}_.
These properties are defined on `ReferenceError.prototype` and shared by all `ReferenceError` instances.
- {{jsxref("Object/constructor", "ReferenceError.prototype.constructor")}}
- : The constructor function that created the instance object. For `ReferenceError` instances, the initial value is the {{jsxref("ReferenceError/ReferenceError", "ReferenceError")}} constructor.
- {{jsxref("Error/name", "ReferenceError.prototype.name")}}
- : Represents the name for the type of error. For `ReferenceError.prototype.name`, the initial value is `"ReferenceError"`.
## Instance methods
_Inherits instance methods from its parent {{jsxref("Error")}}_.
## Examples
### Catching a ReferenceError
```js
try {
let a = undefinedVariable;
} catch (e) {
console.log(e instanceof ReferenceError); // true
console.log(e.message); // "undefinedVariable is not defined"
console.log(e.name); // "ReferenceError"
console.log(e.stack); // Stack of the error
}
```
### Creating a ReferenceError
```js
try {
throw new ReferenceError("Hello");
} catch (e) {
console.log(e instanceof ReferenceError); // true
console.log(e.message); // "Hello"
console.log(e.name); // "ReferenceError"
console.log(e.stack); // Stack of the error
}
```
## Specifications
{{Specifications}}
## Browser compatibility
{{Compat}}
## See also
- {{jsxref("Error")}}