How can I perform a JavaScript zip operation to combine two arrays into one array of paired elements?

General Discussions
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1

Given these arrays:

var a = [1, 2, 3];
var b = ['a', 'b', 'c'];
I want to get this result:

[[1, 'a'], [2, 'b'], [3, 'c']];

What’s the best way to do a JavaScript zip to merge arrays like this?

2

The most straightforward way is a for loop iterating through the shortest array length and pairing elements manually:

function zip(arr1, arr2) {
  const length = Math.min(arr1.length, arr2.length);
  const result = [];
  for (let i = 0; i < length; i++) {
    result.push([arr1[i], arr2[i]]);
  }
  return result;
}

console.log(zip(a, b));
3

If you know both arrays are the same length, you can use .map() on one array and pair with the corresponding index from the other:

const zipped = a.map((val, idx) => [val, b[idx]]);
console.log(zipped);
4

Another approach is to use Array.from with the length of the shortest array, creating the zipped array in a functional style:

const length = Math.min(a.length, b.length);
const zipped = Array.from({ length }, (_, i) => [a[i], b[i]]);
console.log(zipped);

This method is clean, flexible, and works well with dynamic array sizes.