JavaScript - concatenate multiple arrays

In this article, we would like to show you how to concatenate multiple arrays in JavaScript​​​​​.

1. Using concat() method

In this example, we use concat() method to concatenate multiple arrays. 

// ONLINE-RUNNER:browser;

const array1 = ['a', 'b'];
const array2 = ['c', 'd'];
const array3 = ['e', 'f'];
const array4 = ['g', 'h'];

const resultArray = array1.concat(array2, array3, array4);

console.log(resultArray);  // ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h']

2. Using ES6 spread syntax

In this example, we use the spread syntax (...) to concatenate multiple arrays.

// ONLINE-RUNNER:browser;

const array1 = ['a', 'b'];
const array2 = ['c', 'd'];
const array3 = ['e', 'f'];
const array4 = ['g', 'h'];

const resultArray = [...array1, ...array2, ...array3, ...array4 ];

console.log(resultArray);  // ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h']

See also

1. JavaScript - merge two arrays

References

1. Spread syntax (...) - JavaScript | MDN
2. Array.prototype.concat() - JavaScript | MDN