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---
title: Map.prototype.get()
short-title: get()
slug: Web/JavaScript/Reference/Global_Objects/Map/get
page-type: javascript-instance-method
browser-compat: javascript.builtins.Map.get
sidebar: jsref
---
The **`get()`** method of {{jsxref("Map")}} instances returns the value corresponding to the key in this `Map`, or `undefined` if there is none. Object values are returned as the same reference that was originally stored, not as a copy, so mutations to the returned object will be reflected anywhere that reference is held, including inside the `Map`.
{{InteractiveExample("JavaScript Demo: Map.prototype.get()")}}
```js interactive-example
const map = new Map();
map.set("bar", "foo");
console.log(map.get("bar"));
// Expected output: "foo"
console.log(map.get("baz"));
// Expected output: undefined
```
## Syntax
```js-nolint
get(key)
```
### Parameters
- `key`
- : The key of the value to return from the `Map` object. Object keys are compared by [reference](/en-US/docs/Glossary/Object_reference), not by value.
### Return value
The value associated with the specified key in the `Map` object. If the key can't be found, {{jsxref("undefined")}} is returned.
## Examples
### Using get()
```js
const myMap = new Map();
myMap.set("bar", "foo");
console.log(myMap.get("bar")); // Returns "foo"
console.log(myMap.get("baz")); // Returns undefined
```
### Using get() to retrieve a reference to an object
```js
const arr = [];
const myMap = new Map();
myMap.set("bar", arr);
myMap.get("bar").push("foo");
console.log(arr); // ["foo"]
console.log(myMap.get("bar")); // ["foo"]
```
## Specifications
{{Specifications}}
## Browser compatibility
{{Compat}}
## See also
- {{jsxref("Map")}}
- {{jsxref("Map.prototype.delete()")}}
- {{jsxref("Map.prototype.set()")}}
- {{jsxref("Map.prototype.has()")}}
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