Run results for: flat vs forEach

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser: Chrome 131

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

forEach()

809/s

flat()

416/s

View exact numbers

Test name	Executions per second
✓ forEach()	809 Ops/sec
flat()	416 Ops/sec

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

const createNestedArray = (depth, width) => {
  let arr = [];
  for (let i = 0; i < width; i++) {
    arr.push(Array.from({ length: depth }, (_, j) => j));
  }
  return arr;
};

const depth = 1000;
const width = 100;
const nestedArray = createNestedArray(depth, width);

Tests:

flat()
nestedArray.flat();
forEach()
const flattened = []; nestedArray.forEach(subArray => { flattened.push(...subArray); });