Run results for: isArray

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:133.0) Gecko/20100101 Firefox/133.0

Browser: Firefox 133

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

Array.isArray

369.6M/s

[].constructor

129.2M/s

instanceof

128.2M/s

Object.prototype.toString

89.1M/s

View exact numbers

Test name	Executions per second
✓ Array.isArray	369,629,920 Ops/sec
[].constructor	129,223,312 Ops/sec
instanceof	128,227,592 Ops/sec
Object.prototype.toString	89,074,664 Ops/sec

Script Preparation code:

var toStr = Object.prototype.toString
	
function toStrCase(obj){
  return toStr.call(obj) === '[object Array]'
}
function consCase(obj){
  return obj && obj.constructor === Array
}
function instCase(obj){
  return obj && obj instanceof Array
}
var isArray = Array.isArray

Tests:

Array.isArray
isArray([])
instanceof
instCase([])
[].constructor
consCase([])
Object.prototype.toString
toStrCase([])

Array.isArray vs Object.prototype.toString vs [].constructor vs instanceof

Array.isArray

instanceof

[].constructor

Object.prototype.toString