How to Compare an Array of Numbers in JavaScript

Nov 16, 2021

To check if two arrays of numbers are identical, you can use the every() function as shown below.

const array1 = [1, 1, 1, 1, 1];
const array2 = [1, 1, 1, 1, 1];
const array3 = [1, 2, 3, 4, 5, 6];

function numberArrayEquals(array1, array2) {
  return array1.length === array2.length &&
    array1.every((v, i) => array2[i] == array1[i]);
}

numberArrayEquals(array1, array2); // true
numberArrayEquals(array1, array3); // false

Alternative Using JSON.stringify()

You can also use JSON.stringify() to check if the two arrays are identical.

const array1 = [1, 1, 1, 1, 1];
const array2 = [1, 1, 1, 1, 1];
const array3 = [1, 2, 3, 4, 5, 6];
// JSON.stringify(array1) => "[1,1,1,1,1]"
JSON.stringify(array1) === JSON.stringify(array2); // true
JSON.stringify(array1) === JSON.stringify(array3); // false

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