Run results for: set.has vs. array.includes vs plain object (100 000)

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser: Chrome 132

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Object access

34.6M/s

Set.has

24.5M/s

Array.includes (best scenario)

20.0M/s

Array.includes (middle scenario)

53K/s

Array.includes (worst scenario)

27K/s

View exact numbers

Test name	Executions per second
✓ Object access	34,589,364 Ops/sec
Set.has	24,463,558 Ops/sec
Array.includes (best scenario)	20,022,028 Ops/sec
Array.includes (middle scenario)	53,375 Ops/sec
Array.includes (worst scenario)	26,713 Ops/sec

Script Preparation code:

var length = 100000;
var a = Array.from({
    length
}, (e, i) => i+1);
var b = new Set(a);
var c = Object.fromEntries(a.map(e => [e, true]));
var best = 1;
var worst = length;
var middle = length / 2;

Tests:

Array.includes (best scenario)
return a.includes(best)
Set.has
return b.has(best)
Object access
return c[best]
Array.includes (middle scenario)
return a.includes(middle)
Array.includes (worst scenario)
return a.includes(worst)