Run results for: typeof undefined vs falsey check

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/118.0.0.0 Safari/537.36

Browser: Chrome 118

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

typeof

13.6M/s

negate

13.5M/s

View exact numbers

Test name	Executions per second
✓ typeof	13,585,775 Ops/sec
negate	13,471,584 Ops/sec

Script Preparation code:

const undef = undefined
function checkType(val) {
  return typeof val === 'undefined'
}
function negate(val) {
  return !!val
}

Tests: