Run results for: Array.includes vs. Object key lookup vs. Set.has

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36

Browser: Chrome 139

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 7 months ago

Set.has

254.5M/s

key lookup

246.4M/s

includes

130.5M/s

View exact numbers

Test name	Executions per second
✓ Set.has	254,486,272 Ops/sec
key lookup	246,438,320 Ops/sec
includes	130,454,528 Ops/sec

Script Preparation code:

var a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
var b = {1: true, 2: true, 3: true, 4: true, 5: true, 6: true, 7: true, 8: true, 9: true, 10: true}
var c = new Set(a);

Tests:

includes
return a.includes(9)
key lookup
return !!b['9']
Set.has
return c.has(9)