Run results for: empty an array in JavaScript - [] vs setting length

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:137.0) Gecko/20100101 Firefox/137.0

Browser: Firefox 137

Operating system: Windows

Device Platform: Desktop

Date tested: 18 hours ago

Test name	Executions per second
Set length to zero	52476.4 Ops/sec
New empty array	70403.7 Ops/sec

Tests:

Set length to zero
var size = 10000; var arr2 = []; for (var i = 0; i < size; i++){ arr2.push(i); } arr2.length = 0;
New empty array
var size = 10000; var arr3 = []; for (var i = 0; i < size; i++){ arr3.push(i); } arr3 = [];