Run results for: Null check vs typeof

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36

Browser: Chrome 87

Operating system: Linux

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
typeof	13601240.0 Ops/sec
null check	13813690.0 Ops/sec

Script Preparation code:

var a = undefined;
if (Math.random() > 0.5) {
  a = 3;
}

Tests: