JavaScript Array.of() Method

What You’ll Learn

Array.of() is a static method that builds a new array from the values you pass as arguments. It avoids the confusing behavior of Array(7) (length-only array) versus Array.of(7) ([7]). This tutorial covers syntax, five examples, comparisons, and when to prefer literals or Array.from().

Introduction

Most of the time you create arrays with literals: [1, 2, 3]. But the legacy Array() constructor has a trap: a single number argument sets length, not the element value. Array.of() was added in ES2015 to create arrays predictably from any list of arguments.

Think of Array.of as “make an array containing exactly these values”—whether you pass zero, one, or many arguments.

Understanding the Array.of() Method

Array.of(element0, element1, ...) returns a new dense array. Each argument becomes an element at the next index. There is no special case for a lone number: Array.of(5) is [5], not an array of length 5.

This is the counterpart to Array.from(), which builds arrays from iterables or array-like objects. Use of when you already have individual values; use from when converting another collection.

📝 Syntax

General form of the static Array.of method:

Array.of(element0, element1, /* ... , */ elementN)

Parameters

• element0, element1, ... — zero or more values; each becomes one array element.

Return value

• A new Array instance containing the arguments.
• Array.of() with no arguments returns [].

Common patterns

• Array.of(1, 2, 3) — list of values.
• Array.of(42) — single-element array [42].
• Array.of(...items) — copy spread values into a new array.
• Array.of(x, y, z) instead of new Array(x, y, z) for clarity.

Examples Gallery

Open DevTools Console (F12) or use Try-it labs. Example N maps to ?tryit=N.

const numbers = Array.of(1, 2, 3, 4, 5);

console.log(numbers);
// [1, 2, 3, 4, 5]

console.log(Array.isArray(numbers));
// true

[1, 2, 3, 4, 5]
true

console.log(Array.of(7));
// [7] — one element

console.log(Array(7));
// [empty × 7] — length 7, no elements

console.log(Array(7).length);
// 7

console.log(Array.of(7).length);
// 1

[7]
[empty × 7]
7
1

const empty = Array.of();

console.log(empty);
// []

console.log(empty.length);
// 0

[]
0

const mixed = Array.of("hello", 42, true, null, undefined);

console.log(mixed);
// ["hello", 42, true, null, undefined]

console.log(mixed.length);
// 5

["hello", 42, true, null, undefined]
5

function toArray(...items) {
  return Array.of(...items);
}

const scores = toArray(88, 92, 76);

console.log(scores);
// [88, 92, 76]

console.log(scores.length);
// 3

[88, 92, 76]
3

🚀 Common Use Cases

• Single numeric element — Array.of(n) instead of Array(n).
• Factory helpers — wrap rest args into a new array copy.
• Consistent APIs — always return real arrays from functions.
• Testing — build fixture arrays without constructor surprises.
• Functional style — pair with spread when composing data pipelines.
• Teaching — demonstrate static vs instance Array methods.

📝 Notes

• Static method—call Array.of(), not on an instance.
• Fixes the Array(n) single-number length quirk.
• Does not convert iterables—use Array.from() for strings, Sets, etc.
• Literals [a, b, c] remain preferred for fixed lists in source code.
• Array.of(1, 2) and new Array(1, 2) both yield [1, 2].
• ES2015—not available in IE without a polyfill.

💡 Best Practices