Run results for: Chunk array from vs reduce vs for

Test name	Executions per second
✓ Array from	1,608,014 Ops/sec
reduce	1,112,611 Ops/sec
another for	688,655 Ops/sec
for	685,242 Ops/sec
one more	681,863 Ops/sec
last for loop	561,855 Ops/sec
okay real last	378,925 Ops/sec

Array from

const result = Array.from({ length: Math.ceil(elements.length / size) }, (_, i) => elements.slice(i * size, (i + 1) * size));

reduce

const result = elements.reduce(
  (elems, elem, i) => i % size === 0 ? [...elems, [elem]]: [...elems.slice(0, -1), [...elems[elems.length - 1], elem]],
  []
);

for

const result = [];
for (let i = 0; i < elements.length; ++i) {
  if (i % size === 0) result.push([elements[i]]);
  else result[result.length - 1].push(elements[i]);
}

another for

const result = [];
for (let i = 0; i < elements.length; ++i) {
  if (i % size === 0) result.push([]);
  result[result.length - 1].push(elements[i]);
}

one more

const result = [];
let index = -1;
for (let i = 0; i < elements.length; ++i) {
  if (i % size === 0) {
    index += 1;
    result.push([elements[i]]);
  } else result[index].push(elements[i]);
}

last for loop

const result = Array(Math.ceil(elements.length / size)).fill().map(() => Array(size));
let index = -1;
let subIndex = 0;
for (let i = 0; i < elements.length; ++i) {
  if (i % size === 0) {
    index++;
    subIndex = 0;
  }
  result[index][subIndex] = elements[i];
  subIndex++;
}

okay real last

const result = Array(Math.ceil(elements.length / size)).fill().map(() => Array(size));
for (let i = 0; i < elements.length; ++i) {
  result[Math.floor(i / size)][i % size] = elements[i];
}