Run results for: object key vs indexof

Run details:

User agent: Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.99 Safari/537.36

Browser: Chrome 54

Operating system: Windows 8.1

Device Platform: Other

Date tested: 7 years ago

Test name	Executions per second
loop lookup	1528826.9 Ops/sec
array indexed	2453395.8 Ops/sec
key lookup	4988056.0 Ops/sec

Script Preparation code:

var a = [{"id":7,"h":76},{"id":4,"h":34},{"id":9,"h":89}];
var b = [];
for(var i=0;i<a.length;i++)b[i] = a[i].id;
var c = [];
for(var i=0;i<a.length;i++)c[a[i].id] = a[i];

Tests:

loop lookup
for(var i in a)if(i.id==9)return i;
array indexed
return a[b.indexOf(9)];
key lookup
return c[9];

Run results for: object key vs indexof

loop lookup

array indexed

key lookup