Run results for: undefined vs. typeof vs. in vs. hasOwnProperty - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (Android 12; Mobile; rv:96.0) Gecko/96.0 Firefox/96.0

Browser: Firefox Mobile 96

Operating system: Android

Device Platform: Mobile

Date tested: 2 years ago

Test name	Executions per second
undefined	540453400.0 Ops/sec
typeof	541038200.0 Ops/sec
in	540491500.0 Ops/sec
hasOwnProperty	541021100.0 Ops/sec
bool	541962200.0 Ops/sec

Website performance monitoring

Script Preparation code:

var obj = { a: 1, b: 2, c: 3, d: 4, e: 5 };

Tests:

undefined
undefined !== obj.d;
typeof
'undefined' !== typeof obj.d;
in
'd' in obj;
hasOwnProperty
obj.hasOwnProperty( 'd' );
bool
!! obj.d;