Run results for: map vs. for vs. for in vs. forEach - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/104.0.0.0 Safari/537.36

Browser: Chrome 104

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
map	12686970.0 Ops/sec
for in	1654258.0 Ops/sec
for	1638857.0 Ops/sec
forEach	10068050.0 Ops/sec

Website performance monitoring

Script Preparation code:

var a = ["foo", "bar", "baz", "boom"]

Tests:

map
var b = a.map(function(c) { return c; });
for in
var b = []; for (var i in a) { b.push(a[i]); }
for
var b = []; for (var i = 0; i < a.length; i++) { b.push(a[i]); }
forEach
var b = []; a.forEach(function(c) { b.push(c); });