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How to Get All Keys and Values of Object in JavaScript

JavaScript provides three convenient methods for working with objects:

MethodDescriptionReturns
Object.keys()Get all keys of objectstring[]
Object.values()Get all values of objectany[]
Object.entries()Get all pairs[key, value][]

Get All Keys

const user = { name: "Alice", age: 25, role: "admin" };

const keys = Object.keys(user);
console.log(keys); // ["name", "age", "role"]

Get All Values

const values = Object.values(user);
console.log(values); // ["Alice", 25, "admin"]

Get Key-Value Pairs

const entries = Object.entries(user);
console.log(entries);
// [["name", "Alice"], ["age", 25], ["role", "admin"]]

Iterating Over Object

Using for...of and Object.entries():

for (const [key, value] of Object.entries(user)) {
  console.log(`${key}: ${value}`);
}

Using for...in (less recommended):

for (const key in user) {
  if (user.hasOwnProperty(key)) {
    console.log(`${key}: ${user[key]}`);
  }
}

for...in enumerates all enumerable properties, including inherited ones. So you need to use hasOwnProperty.

Important:

Order of keys in object is not strictly guaranteed (but in practice — stable in modern browsers).

Summary

  • Object.keys() — get keys
  • Object.values() — get values
  • Object.entries() — get key-value pairs

These are basic methods for everyday work with objects in JavaScript.