JavaScript Array flat()

Create a new array with the sub-array elements concatenated:

const myArr = [[1,2],[3,4],[5,6]];
const newArr = myArr.flat();

const myArr = [1, 2, [3, [4, 5, 6], 7], 8];
const newArr = myArr.flat(2);

Description

The flat() method concatenates sub-array elements.

array.flat(depth)

Parameter	Description
depth	Optional. How deep a nested array should be flattened. Default is 1.

Type	Description
An array	The flattened array.

JavaScript Array flat() is supported in all modern browsers since January 2020:


Chrome 69	Edge 79	Firefox 62	Safari 12	Opera 56
Sep 2018	Jan 2020	Sep 2018	Sep 2018	Sep 2018