Convert a Map to an Object in JavaScript

# Convert a Map to an Object in JavaScript

To convert a Map to an object, call the Object.fromEntries() method passing it the Map as a parameter.

The Object.fromEntries method takes an iterable, such as a Map, and returns an object containing the key-value pairs of the iterable.

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const map = new Map([
  ['name', 'Bobby'],
  ['country', 'Chile'],
]);

// ✅ Convert Map to Object
const obj = Object.fromEntries(map);
console.log(obj); // 👉️ {name: 'Bobby', country: 'Chile'}

// ✅ Convert Object to Map
const newMap = new Map(Object.entries(obj));
console.log(newMap); // 👉️ {'name' => 'Bobby', 'country' => 'Chile'}

The Object.fromEntries() method takes an array of key-value pairs or a Map object and converts the value to an object

Here's an example of using the Object.fromEntries() method with an array of key-value pairs instead.

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const obj = Object.fromEntries([
  ['name', 'Bobby'],
  ['country', 'Chile'],
]);

console.log(obj); // 👉️ {name: 'Bobby', country: 'Chile'}

The Object.fromEntries() method takes a two-dimensional array of key-value pairs and converts it to an object in the same way it handles a Map.

# Convert a Map to an Object using Map.forEach()

This is a three-step process:

1. Declare a new variable and initialize it to an empty object.
2. Use the Map.forEach() method to iterate over the Map.
3. Assign each key-value pair to the new object.

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const map = new Map([
  ['name', 'Bobby'],
  ['country', 'Chile'],
]);

const obj = {};

map.forEach((value, key) => {
  obj[key] = value;
});

// 👇️ { name: 'Bobby', country: 'Chile' }
console.log(obj);

The function we passed to the Map.forEach() method gets called for each key-value pair of the Map and gets passed the following parameters:

1. value - the value of the iteration
2. key - the key of the iteration
3. map - the Map object that's being iterated

On each iteration, we assign the current key-value pair to the new object.

# Convert a Map to an Object using for...of

This is a three-step process:

1. Declare a new variable and initialize it to an empty object.
2. Use the for...of loop to iterate over the Map.
3. Assign each key-value pair to the new object.

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const map = new Map([
  ['name', 'Bobby'],
  ['country', 'Chile'],
]);

const obj = {};

for (const [key, value] of map) {
  obj[key] = value;
}

// 👇️ { name: 'Bobby', country: 'Chile' }
console.log(obj);

The for...of statement is used to loop over iterable objects like arrays, strings, Map, Set and NodeList objects and generators.

On each iteration, we assign the current key-value pair to the new object.

After the last iteration, all key-value pairs of the Map are stored in the object.

# Additional Resources

You can learn more about the related topics by checking out the following tutorials:

• Convert a Map to an Array of Objects in JavaScript
• How to Convert a Map to JSON in JavaScript
• Convert Map Keys and Values to an Array in JavaScript
• How to convert an Object to a Map in JavaScript
• Convert Bytes to KB, MB, GB or TB using JavaScript